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1If you read this file _as_is_, just ignore the funny characters you see.
2It is written in the POD format (see pod/perlpod.pod) which is specially
3designed to be readable as is.
4
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5=head1 NAME
6
7df75831 7Install - Build and Installation guide for perl 5.
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8
9=head1 SYNOPSIS
10
7df75831 11First, make sure you have an up-to-date version of Perl. If you
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12didn't get your Perl source from CPAN, check the latest version at
13http://www.cpan.org/src/. Perl uses a version scheme where even-numbered
08854360 14subreleases (like 5.8.x and 5.10.x) are stable maintenance releases and
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15odd-numbered subreleases (like 5.7.x and 5.9.x) are unstable
16development releases. Development releases should not be used in
17production environments. Fixes and new features are first carefully
18tested in development releases and only if they prove themselves to be
19worthy will they be migrated to the maintenance releases.
3ce0d271 20
7df75831 21The basic steps to build and install perl 5 on a Unix system with all
dd3196cd 22the defaults are to run, from a freshly unpacked source tree:
8e07c86e 23
491517e0 24 sh Configure -de
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25 make
26 make test
27 make install
36477c24 28
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29Each of these is explained in further detail below.
30
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31The above commands will install Perl to /usr/local (or some other
32platform-specific directory -- see the appropriate file in hints/.)
7df75831 33If that's not okay with you, you can run Configure interactively, by
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34just typing "sh Configure" (without the -de args). You can also specify
35any prefix location by adding "-Dprefix='/some/dir'" to Configure's args.
36To explicitly name the perl binary, use the command
37"make install PERLNAME=myperl".
491517e0 38
ff52061e 39These options, and many more, are explained in further detail below.
7f678428 40
8d74ce1c 41If you have problems, corrections, or questions, please see
ff52061e 42L<"Reporting Problems"> below.
8d74ce1c 43
7beaa944 44For information on what's new in this release, see the
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45pod/perl5110delta.pod file. For more information about how to find more
46specific detail about changes, see the Changes file.
c3edaffb 47
1ec51d55 48=head1 DESCRIPTION
edb1cbcb 49
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50This document is written in pod format as an easy way to indicate its
51structure. The pod format is described in pod/perlpod.pod, but you can
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52read it as is with any pager or editor. Headings and items are marked
53by lines beginning with '='. The other mark-up used is
54
55 B<text> embolden text, used for switches, programs or commands
56 C<code> literal code
57 L<name> A link (cross reference) to name
ce80d64e 58 F<file> A filename
1ec51d55 59
c42e3e15 60Although most of the defaults are probably fine for most users,
ce80d64e 61you should probably at least skim through this document before
1ec51d55 62proceeding.
c3edaffb 63
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64In addition to this file, check if there is a README file specific to
65your operating system, since it may provide additional or different
66instructions for building Perl. If there is a hint file for your
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67system (in the hints/ directory) you might also want to read it
68for even more information.
c42e3e15 69
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70For additional information about porting Perl, see the section on
71L<"Porting information"> below, and look at the files in the Porting/
72directory.
d56c5707 73
ce80d64e 74=head1 PRELIMINARIES
c42e3e15 75
ce80d64e 76=head2 Changes and Incompatibilities
c42e3e15 77
4eeeaff6 78Please see pod/perl5110delta.pod for a description of the changes and
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79potential incompatibilities introduced with this release. A few of
80the most important issues are listed below, but you should refer
4eeeaff6 81to pod/perl5110delta.pod for more detailed information.
c42e3e15 82
fdd3cf50 83B<WARNING:> This version is not binary compatible with prior releases of Perl.
cc65bb49 84If you have built extensions (i.e. modules that include C code)
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85using an earlier version of Perl, you will need to rebuild and reinstall
86those extensions.
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87
88Pure perl modules without XS or C code should continue to work fine
dd3196cd 89without reinstallation. See the discussion below on
7df75831 90L<"Coexistence with earlier versions of perl 5"> for more details.
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91
92The standard extensions supplied with Perl will be handled automatically.
93
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94On a related issue, old modules may possibly be affected by the changes
95in the Perl language in the current release. Please see
4eeeaff6 96pod/perl5110delta.pod for a description of what's changed. See your
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97installed copy of the perllocal.pod file for a (possibly incomplete)
98list of locally installed modules. Also see CPAN::autobundle for one
99way to make a "bundle" of your currently installed modules.
16dc217a 100
aa689395 101=head1 Run Configure
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102
103Configure will figure out various things about your system. Some
104things Configure will figure out for itself, other things it will ask
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105you about. To accept the default, just press RETURN. The default is
106almost always okay. It is normal for some things to be "NOT found",
107since Configure often searches for many different ways of performing
108the same function.
109
ce80d64e 110At any Configure prompt, you can type &-d and Configure will use the
d6baa268 111defaults from then on.
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112
113After it runs, Configure will perform variable substitution on all the
1ec51d55 114*.SH files and offer to run make depend.
8e07c86e 115
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116The results of a Configure run are stored in the config.sh and Policy.sh
117files.
118
ce80d64e 119=head2 Common Configure options
844fc9f4 120
ce80d64e 121Configure supports a number of useful options. Run
844fc9f4 122
ce80d64e 123 Configure -h
d6baa268 124
ce80d64e 125to get a listing. See the Porting/Glossary file for a complete list of
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126Configure variables you can set and their definitions.
127
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128=over 4
129
08854360 130=item C compiler
d6baa268 131
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132To compile with gcc, if it's not the default compiler on your
133system, you should run
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134
135 sh Configure -Dcc=gcc
136
08854360 137This is the preferred way to specify gcc (or any another alternative
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138compiler) so that the hints files can set appropriate defaults.
139
d6baa268 140=item Installation prefix
4633a7c4 141
8e07c86e 142By default, for most systems, perl will be installed in
8d74ce1c 143/usr/local/{bin, lib, man}. (See L<"Installation Directories">
7df75831 144and L<"Coexistence with earlier versions of perl 5"> below for
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145further details.)
146
147You can specify a different 'prefix' for the default installation
ce80d64e 148directory when Configure prompts you, or by using the Configure command
8d74ce1c 149line option -Dprefix='/some/directory', e.g.
8e07c86e 150
25f94b33 151 sh Configure -Dprefix=/opt/perl
4633a7c4 152
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153If your prefix contains the string "perl", then the suggested
154directory structure is simplified. For example, if you use
155prefix=/opt/perl, then Configure will suggest /opt/perl/lib instead of
156/opt/perl/lib/perl5/. Again, see L<"Installation Directories"> below
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157for more details. Do not include a trailing slash, (i.e. /opt/perl/)
158or you may experience odd test failures.
8e07c86e 159
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160NOTE: You must not specify an installation directory that is the same
161as or below your perl source directory. If you do, installperl will
162attempt infinite recursion.
84902520 163
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164=item /usr/bin/perl
165
166It may seem obvious, but Perl is useful only when users can easily
167find it. It's often a good idea to have both /usr/bin/perl and
dd64f1c3 168/usr/local/bin/perl be symlinks to the actual binary. Be especially
d6baa268 169careful, however, not to overwrite a version of perl supplied by your
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170vendor unless you are sure you know what you are doing. If you insist
171on replacing your vendor's perl, useful information on how it was
172configured may be found with
173
174 perl -V:config_args
175
176(Check the output carefully, however, since this doesn't preserve
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177spaces in arguments to Configure. For that, you have to look carefully
178at config_arg1, config_arg2, etc.)
d6baa268 179
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180By default, Configure will not try to link /usr/bin/perl to the current
181version of perl. You can turn on that behavior by running
d6baa268 182
7d56c962 183 Configure -Dinstallusrbinperl
d6baa268 184
7d56c962 185or by answering 'yes' to the appropriate Configure prompt.
d6baa268 186
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187In any case, system administrators are strongly encouraged to put
188(symlinks to) perl and its accompanying utilities, such as perldoc,
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189into a directory typically found along a user's PATH, or in another
190obvious and convenient place.
191
71c4561b 192=item Building a development release
04d420f9 193
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194For development releases (odd subreleases, like 5.9.x) if you want to
195use Configure -d, you will also need to supply -Dusedevel to Configure,
196because the default answer to the question "do you really want to
197Configure a development version?" is "no". The -Dusedevel skips that
198sanity check.
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199
200=back
8e07c86e 201
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202If you are willing to accept all the defaults, and you want terse
203output, you can run
204
205 sh Configure -des
206
dd3196cd 207=head2 Altering Configure variables for C compiler switches etc.
46bb10fb 208
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209For most users, most of the Configure defaults are fine, or can easily
210be set on the Configure command line. However, if Configure doesn't
211have an option to do what you want, you can change Configure variables
212after the platform hints have been run by using Configure's -A switch.
213For example, here's how to add a couple of extra flags to C compiler
214invocations:
46bb10fb 215
08854360 216 sh Configure -Accflags="-DPERL_EXTERNAL_GLOB -DNO_HASH_SEED"
46bb10fb 217
5247441a 218To clarify, those ccflags values are not Configure options; if passed to
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219Configure directly, they won't do anything useful (they will define a
220variable in config.sh, but without taking any action based upon it).
221But when passed to the compiler, those flags will activate #ifdefd code.
5247441a 222
ce80d64e 223For more help on Configure switches, run
46bb10fb 224
ce80d64e 225 sh Configure -h
46bb10fb 226
ce80d64e 227=head2 Major Configure-time Build Options
46bb10fb 228
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229There are several different ways to Configure and build perl for your
230system. For most users, the defaults are sensible and will work.
231Some users, however, may wish to further customize perl. Here are
232some of the main things you can change.
46bb10fb 233
ce80d64e 234=head3 Threads
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236On some platforms, perl can be compiled with support for threads. To
237enable this, run
4633a7c4 238
ce80d64e 239 sh Configure -Dusethreads
4633a7c4 240
ce80d64e 241The default is to compile without thread support.
cc65bb49 242
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243Perl used to have two different internal threads implementations. The current
244model (available internally since 5.6, and as a user-level module since 5.8) is
245called interpreter-based implementation (ithreads), with one interpreter per
246thread, and explicit sharing of data. The (deprecated) 5.005 version
54c46bd5 247(5005threads) was removed for release 5.10.
d6baa268 248
ce80d64e 249The 'threads' module is for use with the ithreads implementation. The
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250'Thread' module emulates the old 5005threads interface on top of the current
251ithreads model.
d6baa268 252
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253When using threads, perl uses a dynamically-sized buffer for some of
254the thread-safe library calls, such as those in the getpw*() family.
255This buffer starts small, but it will keep growing until the result
256fits. To get a fixed upper limit, you should compile Perl with
257PERL_REENTRANT_MAXSIZE defined to be the number of bytes you want. One
258way to do this is to run Configure with
08854360 259C<-Accflags=-DPERL_REENTRANT_MAXSIZE=65536>.
d6baa268 260
08854360 261=head3 Large file support
b367e8b0 262
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263Since Perl 5.6.0, Perl has supported large files (files larger than
2642 gigabytes), and in many common platforms like Linux or Solaris this
265support is on by default.
d6baa268 266
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267This is both good and bad. It is good in that you can use large files,
268seek(), stat(), and -s them. It is bad in that if you are interfacing Perl
269using some extension, the components you are connecting to must also
270be large file aware: if Perl thinks files can be large but the other
271parts of the software puzzle do not understand the concept, bad things
08854360 272will happen.
d6baa268 273
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274There's also one known limitation with the current large files
275implementation: unless you also have 64-bit integers (see the next
276section), you cannot use the printf/sprintf non-decimal integer formats
277like C<%x> to print filesizes. You can use C<%d>, though.
d6baa268 278
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279If you want to compile perl without large file support, use
280
281 sh Configure -Uuselargefiles
282
08854360 283=head3 64 bit support
d6baa268 284
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285If your platform does not run natively at 64 bits, but can simulate
286them with compiler flags and/or C<long long> or C<int64_t>,
ce80d64e 287you can build a perl that uses 64 bits.
d6baa268 288
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289There are actually two modes of 64-bitness: the first one is achieved
290using Configure -Duse64bitint and the second one using Configure
291-Duse64bitall. The difference is that the first one is minimal and
292the second one maximal. The first works in more places than the second.
d6baa268 293
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294The C<use64bitint> option does only as much as is required to get
29564-bit integers into Perl (this may mean, for example, using "long
296longs") while your memory may still be limited to 2 gigabytes (because
297your pointers could still be 32-bit). Note that the name C<64bitint>
298does not imply that your C compiler will be using 64-bit C<int>s (it
299might, but it doesn't have to). The C<use64bitint> simply means that
300you will be able to have 64 bit-wide scalar values.
d6baa268 301
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302The C<use64bitall> option goes all the way by attempting to switch
303integers (if it can), longs (and pointers) to being 64-bit. This may
304create an even more binary incompatible Perl than -Duse64bitint: the
305resulting executable may not run at all in a 32-bit box, or you may
306have to reboot/reconfigure/rebuild your operating system to be 64-bit
307aware.
d6baa268 308
08854360 309Natively 64-bit systems need neither -Duse64bitint nor -Duse64bitall.
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310On these systems, it might be the default compilation mode, and there
311is currently no guarantee that passing no use64bitall option to the
312Configure process will build a 32bit perl. Implementing -Duse32bit*
313options is planned for perl 5.12.
d6baa268 314
ce80d64e 315=head3 Long doubles
d6baa268 316
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317In some systems you may be able to use long doubles to enhance the
318range and precision of your double precision floating point numbers
319(that is, Perl's numbers). Use Configure -Duselongdouble to enable
320this support (if it is available).
d6baa268 321
ce80d64e 322=head3 "more bits"
b367e8b0 323
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324You can "Configure -Dusemorebits" to turn on both the 64-bit support
325and the long double support.
b367e8b0 326
ce80d64e 327=head3 Algorithmic Complexity Attacks on Hashes
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328
329In Perls 5.8.0 and earlier it was easy to create degenerate hashes.
330Processing such hashes would consume large amounts of CPU time,
3debabd9 331enabling a "Denial of Service" attack against Perl. Such hashes may be
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332a problem for example for mod_perl sites, sites with Perl CGI scripts
333and web services, that process data originating from external sources.
334
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335In Perl 5.8.1 a security feature was introduced to make it harder to
336create such degenerate hashes. A visible side effect of this was that
337the keys(), values(), and each() functions may return the hash elements
338in different order between different runs of Perl even with the same
339data. It also had unintended binary incompatibility issues with
340certain modules compiled against Perl 5.8.0.
341
342In Perl 5.8.2 an improved scheme was introduced. Hashes will return
343elements in the same order as Perl 5.8.0 by default. On a hash by hash
344basis, if pathological data is detected during a hash key insertion,
345then that hash will switch to an alternative random hash seed. As
346adding keys can always dramatically change returned hash element order,
347existing programs will not be affected by this, unless they
348specifically test for pre-recorded hash return order for contrived
349data. (eg the list of keys generated by C<map {"\0"x$_} 0..15> trigger
350randomisation) In effect the new implementation means that 5.8.1 scheme
351is only being used on hashes which are under attack.
352
353One can still revert to the old guaranteed repeatable order (and be
354vulnerable to attack by wily crackers) by setting the environment
355variable PERL_HASH_SEED, see L<perlrun/PERL_HASH_SEED>. Another option
356is to add -DUSE_HASH_SEED_EXPLICIT to the compilation flags (for
f80da78e 357example by using C<Configure -Accflags=-DUSE_HASH_SEED_EXPLICIT>), in
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358which case one has to explicitly set the PERL_HASH_SEED environment
359variable to enable the security feature, or by adding -DNO_HASH_SEED to
360the compilation flags to completely disable the randomisation feature.
504f80c1 361
3debabd9 362B<Perl has never guaranteed any ordering of the hash keys>, and the
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363ordering has already changed several times during the lifetime of Perl
3645. Also, the ordering of hash keys has always been, and continues to
08854360 365be, affected by the insertion order. Note that because of this
86358043 366randomisation for example the Data::Dumper results will be different
08854360 367between different runs of Perl, since Data::Dumper by default dumps
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368hashes "unordered". The use of the Data::Dumper C<Sortkeys> option is
369recommended.
504f80c1 370
ce80d64e 371=head3 SOCKS
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372
373Perl can be configured to be 'socksified', that is, to use the SOCKS
374TCP/IP proxy protocol library. SOCKS is used to give applications
375access to transport layer network proxies. Perl supports only SOCKS
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376Version 5. The corresponding Configure option is -Dusesocks.
377You can find more about SOCKS from wikipedia at
378L<http://en.wikipedia.org/wiki/SOCKS>.
1b9c9cf5 379
ce80d64e 380=head3 Dynamic Loading
d6baa268 381
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382By default, Configure will compile perl to use dynamic loading.
383If you want to force perl to be compiled completely
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384statically, you can either choose this when Configure prompts you or
385you can use the Configure command line option -Uusedl.
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386With this option, you won't be able to use any new extension
387(XS) module without recompiling perl itself.
d6baa268 388
ce80d64e 389=head3 Building a shared Perl library
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390
391Currently, for most systems, the main perl executable is built by
392linking the "perl library" libperl.a with perlmain.o, your static
8ba4bff0 393extensions, and various extra libraries, such as -lm.
c3edaffb 394
08854360 395On systems that support dynamic loading, it may be possible to
9d67150a 396replace libperl.a with a shared libperl.so. If you anticipate building
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397several different perl binaries (e.g. by embedding libperl into
398different programs, or by using the optional compiler extension), then
9d67150a 399you might wish to build a shared libperl.so so that all your binaries
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400can share the same library.
401
402The disadvantages are that there may be a significant performance
9d67150a 403penalty associated with the shared libperl.so, and that the overall
aa689395 404mechanism is still rather fragile with respect to different versions
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405and upgrades.
406
407In terms of performance, on my test system (Solaris 2.5_x86) the perl
9d67150a 408test suite took roughly 15% longer to run with the shared libperl.so.
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409Your system and typical applications may well give quite different
410results.
411
412The default name for the shared library is typically something like
08854360 413libperl.so.5.8.8 (for Perl 5.8.8), or libperl.so.588, or simply
9d67150a 414libperl.so. Configure tries to guess a sensible naming convention
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415based on your C library name. Since the library gets installed in a
416version-specific architecture-dependent directory, the exact name
417isn't very important anyway, as long as your linker is happy.
418
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419You can elect to build a shared libperl by
420
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421 sh Configure -Duseshrplib
422
423To build a shared libperl, the environment variable controlling shared
424library search (LD_LIBRARY_PATH in most systems, DYLD_LIBRARY_PATH for
425NeXTSTEP/OPENSTEP/Darwin, LIBRARY_PATH for BeOS, LD_LIBRARY_PATH/SHLIB_PATH
426for HP-UX, LIBPATH for AIX, PATH for Cygwin) must be set up to include
427the Perl build directory because that's where the shared libperl will
428be created. Configure arranges makefile to have the correct shared
429library search settings. You can find the name of the environment
430variable Perl thinks works in your your system by
431
432 grep ldlibpthname config.sh
433
434However, there are some special cases where manually setting the
435shared library path might be required. For example, if you want to run
436something like the following with the newly-built but not-yet-installed
437./perl:
438
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439 cd t; ./perl -MTestInit misc/failing_test.t
440
ce80d64e 441or
08854360 442
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443 ./perl -Ilib ~/my_mission_critical_test
444
445then you need to set up the shared library path explicitly.
446You can do this with
447
448 LD_LIBRARY_PATH=`pwd`:$LD_LIBRARY_PATH; export LD_LIBRARY_PATH
449
450for Bourne-style shells, or
451
452 setenv LD_LIBRARY_PATH `pwd`
453
454for Csh-style shells. (This procedure may also be needed if for some
455unexpected reason Configure fails to set up makefile correctly.) (And
456again, it may be something other than LD_LIBRARY_PATH for you, see above.)
457
458You can often recognize failures to build/use a shared libperl from error
459messages complaining about a missing libperl.so (or libperl.sl in HP-UX),
460for example:
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461
462 18126:./miniperl: /sbin/loader: Fatal Error: cannot map libperl.so
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463
464There is also an potential problem with the shared perl library if you
465want to have more than one "flavor" of the same version of perl (e.g.
466with and without -DDEBUGGING). For example, suppose you build and
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467install a standard Perl 5.10.0 with a shared library. Then, suppose you
468try to build Perl 5.10.0 with -DDEBUGGING enabled, but everything else
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469the same, including all the installation directories. How can you
470ensure that your newly built perl will link with your newly built
471libperl.so.8 rather with the installed libperl.so.8? The answer is
472that you might not be able to. The installation directory is encoded
473in the perl binary with the LD_RUN_PATH environment variable (or
474equivalent ld command-line option). On Solaris, you can override that
475with LD_LIBRARY_PATH; on Linux, you can only override at runtime via
476LD_PRELOAD, specifying the exact filename you wish to be used; and on
477Digital Unix, you can override LD_LIBRARY_PATH by setting the
478_RLD_ROOT environment variable to point to the perl build directory.
479
480In other words, it is generally not a good idea to try to build a perl
481with a shared library if $archlib/CORE/$libperl already exists from a
482previous build.
483
484A good workaround is to specify a different directory for the
485architecture-dependent library for your -DDEBUGGING version of perl.
486You can do this by changing all the *archlib* variables in config.sh to
487point to your new architecture-dependent library.
488
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489=head3 Environment access
490
491Perl often needs to write to the program's environment, such as when C<%ENV>
492is assigned to. Many implementations of the C library function C<putenv()>
493leak memory, so where possible perl will manipulate the environment directly
494to avoid these leaks. The default is now to perform direct manipulation
495whenever perl is running as a stand alone interpreter, and to call the safe
496but potentially leaky C<putenv()> function when the perl interpreter is
497embedded in another application. You can force perl to always use C<putenv()>
779ec477 498by compiling with -DPERL_USE_SAFE_PUTENV. You can force an embedded perl to
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499use direct manipulation by setting C<PL_use_safe_putenv = 0;> after the
500C<perl_construct()> call.
501
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502=head2 Installation Directories
503
504The installation directories can all be changed by answering the
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505appropriate questions in Configure. For convenience, all the installation
506questions are near the beginning of Configure. Do not include trailing
507slashes on directory names. At any point during the Configure process,
508you can answer a question with &-d and Configure will use the defaults
509from then on. Alternatively, you can
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510
511 grep '^install' config.sh
512
513after Configure has run to verify the installation paths.
514
515The defaults are intended to be reasonable and sensible for most
516people building from sources. Those who build and distribute binary
517distributions or who export perl to a range of systems will probably
518need to alter them. If you are content to just accept the defaults,
519you can safely skip the next section.
520
521The directories set up by Configure fall into three broad categories.
522
523=over 4
524
525=item Directories for the perl distribution
526
54c46bd5 527By default, Configure will use the following directories for 5.11.0.
ce80d64e 528$version is the full perl version number, including subversion, e.g.
54c46bd5 5295.11.0 or 5.9.5, and $archname is a string like sun4-sunos,
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530determined by Configure. The full definitions of all Configure
531variables are in the file Porting/Glossary.
532
533 Configure variable Default value
534 $prefixexp /usr/local
535 $binexp $prefixexp/bin
536 $scriptdirexp $prefixexp/bin
537 $privlibexp $prefixexp/lib/perl5/$version
538 $archlibexp $prefixexp/lib/perl5/$version/$archname
539 $man1direxp $prefixexp/man/man1
540 $man3direxp $prefixexp/man/man3
541 $html1direxp (none)
542 $html3direxp (none)
543
544$prefixexp is generated from $prefix, with ~ expansion done to convert home
545directories into absolute paths. Similarly for the other variables listed. As
546file system calls do not do this, you should always reference the ...exp
547variables, to support users who build perl in their home directory.
548
549Actually, Configure recognizes the SVR3-style
550/usr/local/man/l_man/man1 directories, if present, and uses those
551instead. Also, if $prefix contains the string "perl", the library
552directories are simplified as described below. For simplicity, only
553the common style is shown here.
554
555=item Directories for site-specific add-on files
556
557After perl is installed, you may later wish to add modules (e.g. from
558CPAN) or scripts. Configure will set up the following directories to
559be used for installing those add-on modules and scripts.
560
561 Configure variable Default value
562 $siteprefixexp $prefixexp
563 $sitebinexp $siteprefixexp/bin
564 $sitescriptexp $siteprefixexp/bin
565 $sitelibexp $siteprefixexp/lib/perl5/site_perl/$version
566 $sitearchexp $siteprefixexp/lib/perl5/site_perl/$version/$archname
567 $siteman1direxp $siteprefixexp/man/man1
568 $siteman3direxp $siteprefixexp/man/man3
569 $sitehtml1direxp (none)
570 $sitehtml3direxp (none)
571
572By default, ExtUtils::MakeMaker will install architecture-independent
573modules into $sitelib and architecture-dependent modules into $sitearch.
574
575=item Directories for vendor-supplied add-on files
576
577Lastly, if you are building a binary distribution of perl for
578distribution, Configure can optionally set up the following directories
579for you to use to distribute add-on modules.
580
581 Configure variable Default value
582 $vendorprefixexp (none)
583 (The next ones are set only if vendorprefix is set.)
584 $vendorbinexp $vendorprefixexp/bin
585 $vendorscriptexp $vendorprefixexp/bin
586 $vendorlibexp
587 $vendorprefixexp/lib/perl5/vendor_perl/$version
588 $vendorarchexp
589 $vendorprefixexp/lib/perl5/vendor_perl/$version/$archname
590 $vendorman1direxp $vendorprefixexp/man/man1
591 $vendorman3direxp $vendorprefixexp/man/man3
592 $vendorhtml1direxp (none)
593 $vendorhtml3direxp (none)
594
595These are normally empty, but may be set as needed. For example,
596a vendor might choose the following settings:
597
598 $prefix /usr
599 $siteprefix /usr/local
600 $vendorprefix /usr
601
602This would have the effect of setting the following:
603
604 $binexp /usr/bin
605 $scriptdirexp /usr/bin
606 $privlibexp /usr/lib/perl5/$version
607 $archlibexp /usr/lib/perl5/$version/$archname
608 $man1direxp /usr/man/man1
609 $man3direxp /usr/man/man3
610
611 $sitebinexp /usr/local/bin
612 $sitescriptexp /usr/local/bin
613 $sitelibexp /usr/local/lib/perl5/site_perl/$version
614 $sitearchexp /usr/local/lib/perl5/site_perl/$version/$archname
615 $siteman1direxp /usr/local/man/man1
616 $siteman3direxp /usr/local/man/man3
617
618 $vendorbinexp /usr/bin
619 $vendorscriptexp /usr/bin
620 $vendorlibexp /usr/lib/perl5/vendor_perl/$version
621 $vendorarchexp /usr/lib/perl5/vendor_perl/$version/$archname
622 $vendorman1direxp /usr/man/man1
623 $vendorman3direxp /usr/man/man3
624
625Note how in this example, the vendor-supplied directories are in the
626/usr hierarchy, while the directories reserved for the end-user are in
627the /usr/local hierarchy.
628
629The entire installed library hierarchy is installed in locations with
630version numbers, keeping the installations of different versions distinct.
631However, later installations of Perl can still be configured to search the
632installed libraries corresponding to compatible earlier versions.
7df75831 633See L<"Coexistence with earlier versions of perl 5"> below for more details
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634on how Perl can be made to search older version directories.
635
636Of course you may use these directories however you see fit. For
637example, you may wish to use $siteprefix for site-specific files that
638are stored locally on your own disk and use $vendorprefix for
639site-specific files that are stored elsewhere on your organization's
640network. One way to do that would be something like
641
642 sh Configure -Dsiteprefix=/usr/local -Dvendorprefix=/usr/share/perl
643
644=item otherlibdirs
645
646As a final catch-all, Configure also offers an $otherlibdirs
647variable. This variable contains a colon-separated list of additional
648directories to add to @INC. By default, it will be empty.
649Perl will search these directories (including architecture and
650version-specific subdirectories) for add-on modules and extensions.
651
652For example, if you have a bundle of perl libraries from a previous
653installation, perhaps in a strange place:
654
655 Configure -Dotherlibdirs=/usr/lib/perl5/site_perl/5.8.1
656
657=item APPLLIB_EXP
658
659There is one other way of adding paths to @INC at perl build time, and
660that is by setting the APPLLIB_EXP C pre-processor token to a colon-
661separated list of directories, like this
662
663 sh Configure -Accflags='-DAPPLLIB_EXP=\"/usr/libperl\"'
664
665The directories defined by APPLLIB_EXP get added to @INC I<first>,
666ahead of any others, and so provide a way to override the standard perl
667modules should you, for example, want to distribute fixes without
668touching the perl distribution proper. And, like otherlib dirs,
669version and architecture specific subdirectories are also searched, if
670present, at run time. Of course, you can still search other @INC
671directories ahead of those in APPLLIB_EXP by using any of the standard
672run-time methods: $PERLLIB, $PERL5LIB, -I, use lib, etc.
673
785aa5e3 674=item usesitecustomize
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675
676Run-time customization of @INC can be enabled with:
677
36de116d 678 sh Configure -Dusesitecustomize
20ef40cf 679
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680which will define USE_SITECUSTOMIZE and $Config{usesitecustomize}.
681When enabled, this makes perl run F<$sitelibexp/sitecustomize.pl> before
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682anything else. This script can then be set up to add additional
683entries to @INC.
684
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685=item Man Pages
686
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687By default, man pages will be installed in $man1dir and $man3dir, which
688are normally /usr/local/man/man1 and /usr/local/man/man3. If you
689want to use a .3pm suffix for perl man pages, you can do that with
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690
691 sh Configure -Dman3ext=3pm
692
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693=item HTML pages
694
695Currently, the standard perl installation does not do anything with
696HTML documentation, but that may change in the future. Further, some
697add-on modules may wish to install HTML documents. The html Configure
698variables listed above are provided if you wish to specify where such
699documents should be placed. The default is "none", but will likely
700eventually change to something useful based on user feedback.
701
702=back
703
704Some users prefer to append a "/share" to $privlib and $sitelib
705to emphasize that those directories can be shared among different
706architectures.
707
708Note that these are just the defaults. You can actually structure the
709directories any way you like. They don't even have to be on the same
710filesystem.
c3edaffb 711
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712Further details about the installation directories, maintenance and
713development subversions, and about supporting multiple versions are
7df75831 714discussed in L<"Coexistence with earlier versions of perl 5"> below.
10c7e831 715
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716If you specify a prefix that contains the string "perl", then the
717library directory structure is slightly simplified. Instead of
718suggesting $prefix/lib/perl5/, Configure will suggest $prefix/lib.
2bf2710f 719
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720Thus, for example, if you Configure with
721-Dprefix=/opt/perl, then the default library directories for 5.9.0 are
2bf2710f 722
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723 Configure variable Default value
724 $privlib /opt/perl/lib/5.9.0
725 $archlib /opt/perl/lib/5.9.0/$archname
726 $sitelib /opt/perl/lib/site_perl/5.9.0
727 $sitearch /opt/perl/lib/site_perl/5.9.0/$archname
2bf2710f 728
ce80d64e 729=head2 Changing the installation directory
c3edaffb 730
ce80d64e 731Configure distinguishes between the directory in which perl (and its
7df75831 732associated files) should be installed, and the directory in which it
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733will eventually reside. For most sites, these two are the same; for
734sites that use AFS, this distinction is handled automatically.
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735However, sites that use package management software such as rpm or
736dpkg, or users building binary packages for distribution may also
737wish to install perl into a different directory before moving perl
738to its final destination. There are two ways to do that:
739
740=over 4
741
742=item installprefix
c3edaffb 743
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744To install perl under the /tmp/perl5 directory, use the following
745command line:
c3edaffb 746
7df75831 747 sh Configure -Dinstallprefix=/tmp/perl5
c3edaffb 748
ce80d64e 749(replace /tmp/perl5 by a directory of your choice).
2bf2710f 750
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751Beware, though, that if you go to try to install new add-on
752modules, they too will get installed in under '/tmp/perl5' if you
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753follow this example. That's why it's usually better to use DESTDIR,
754as shown in the next section.
c3edaffb 755
7df75831 756=item DESTDIR
9d67150a 757
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758If you need to install perl on many identical systems, it is convenient
759to compile it once and create an archive that can be installed on
760multiple systems. Suppose, for example, that you want to create an
761archive that can be installed in /opt/perl. One way to do that is by
762using the DESTDIR variable during C<make install>. The DESTDIR is
763automatically prepended to all the installation paths. Thus you
764simply do:
830717a7 765
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766 sh Configure -Dprefix=/opt/perl -des
767 make
768 make test
769 make install DESTDIR=/tmp/perl5
770 cd /tmp/perl5/opt/perl
771 tar cvf /tmp/perl5-archive.tar .
9d67150a 772
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773=back
774
32878f30 775=head2 Relocatable @INC
776
777To create a relocatable perl tree, use the following command line:
778
779 sh Configure -Duserelocatableinc
780
781Then the paths in @INC (and everything else in %Config) can be
782optionally located via the path of the perl executable.
783
784That means that, if the string ".../" is found at the start of any
785path, it's substituted with the directory of $^X. So, the relocation
786can be configured on a per-directory basis, although the default with
787"-Duserelocatableinc" is that everything is relocated. The initial
788install is done to the original configured prefix.
789
ce80d64e 790=head2 Site-wide Policy settings
55479bb6 791
ce80d64e 792After Configure runs, it stores a number of common site-wide "policy"
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793answers (such as installation directories) in the Policy.sh file.
794If you want to build perl on another system using the same policy
795defaults, simply copy the Policy.sh file to the new system's perl build
796directory, and Configure will use it. This will work even if Policy.sh was
a0a8d9d3 797generated for another version of Perl, or on a system with a
da1b4322 798different architecture and/or operating system. However, in such cases,
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799you should review the contents of the file before using it: for
800example, your new target may not keep its man pages in the same place
801as the system on which the file was generated.
55479bb6 802
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803Alternatively, if you wish to change some or all of those policy
804answers, you should
c3edaffb 805
ce80d64e 806 rm -f Policy.sh
aa689395 807
ce80d64e 808to ensure that Configure doesn't re-use them.
2ae324a7 809
ce80d64e 810Further information is in the Policy_sh.SH file itself.
aa689395 811
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812If the generated Policy.sh file is unsuitable, you may freely edit it
813to contain any valid shell commands. It will be run just after the
814platform-specific hints files.
aa689395 815
ce80d64e 816=head2 Disabling older versions of Perl
aa689395 817
ce80d64e 818Configure will search for binary compatible versions of previously
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819installed perl binaries in the tree that is specified as target tree,
820and these will be used as locations to search for modules by the perl
821being built. The list of perl versions found will be put in the Configure
822variable inc_version_list.
86058a2d 823
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824To disable this use of older perl modules, even completely valid pure perl
825modules, you can specify to not include the paths found:
b2a6d19e 826
ce80d64e 827 sh Configure -Dinc_version_list=none ...
d6baa268 828
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829When using the newer perl, you can add these paths again in the
830$PERL5LIB environment variable or with perl's -I runtime option.
86058a2d 831
ce80d64e 832=head2 Building Perl outside of the source directory
86058a2d 833
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834Sometimes it is desirable to build Perl in a directory different from
835where the sources are, for example if you want to keep your sources
836read-only, or if you want to share the sources between different binary
837architectures. You can do this (if your file system supports symbolic
838links) by
06c896bb 839
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840 mkdir /tmp/perl/build/directory
841 cd /tmp/perl/build/directory
842 sh /path/to/perl/source/Configure -Dmksymlinks ...
06c896bb 843
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844This will create in /tmp/perl/build/directory a tree of symbolic links
845pointing to files in /path/to/perl/source. The original files are left
846unaffected. After Configure has finished you can just say
06c896bb 847
ce80d64e 848 make
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849 make test
850 make install
06c896bb 851
ce80d64e 852as usual, and Perl will be built in /tmp/perl/build/directory.
aa689395 853
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854=head2 Building a debugging perl
855
856You can run perl scripts under the perl debugger at any time with
3fe9a6f1 857B<perl -d your_script>. If, however, you want to debug perl itself,
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858you probably want to have support for perl internal debugging code
859(activated by adding -DDEBUGGING to ccflags), and/or support for the
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860system debugger by adding -g to the optimisation flags. For that,
861use the parameter:
eaf812ae 862
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863 sh Configure -DDEBUGGING
864
865or
866
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867 sh Configure -DDEBUGGING=<mode>
868
869For a more eye appealing call, -DEBUGGING is defined to be an alias
870for -DDEBUGGING. For both, the -U calls are also supported, in order
871to be able to overrule the hints or Policy.sh settings.
872
7df75831 873Here are the DEBUGGING modes:
3bf462b8 874
7df75831 875=over 4
3bf462b8 876
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877=item -DDEBUGGING
878
879=item -DEBUGGING
880
881=item -DEBUGGING=both
882
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883Sets both -DDEBUGGING in the ccflags, and adds -g to optimize.
884
885You can actually specify -g and -DDEBUGGING independently (see below),
886but usually it's convenient to have both.
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887
888=item -DEBUGGING=-g
889
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890=item -Doptimize=-g
891
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892Adds -g to optimize, but does not set -DDEBUGGING.
893
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894(Note: Your system may actually require something like cc -g2.
895Check your man pages for cc(1) and also any hint file for your system.)
896
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897=item -DEBUGGING=none
898
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899=item -UDEBUGGING
900
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901Removes -g from optimize, and -DDEBUGGING from ccflags.
902
903=back
904
3bf462b8 905If you are using a shared libperl, see the warnings about multiple
a522f097 906versions of perl under L<Building a shared Perl library>.
3bf462b8 907
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908Note that a perl built with -DDEBUGGING will be bigger and will run more
909slowly than a standard perl.
910
911=head2 DTrace support
912
913On platforms where DTrace is available, it may be enabled by
914using the -Dusedtrace option to Configure. DTrace probes are available for
915subroutine entry (sub-entry) and subroutine exit (sub-exit). Here's a
916simple D script that uses them:
917
918 perl$target:::sub-entry, perl$target:::sub-return {
919 printf("%s %s (%s:%d)\n", probename == "sub-entry" ? "->" : "<-",
920 copyinstr(arg0), copyinstr(arg1), arg2);
921 }
922
923
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924=head2 Extensions
925
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926Perl ships with a number of standard extensions. These are contained
927in the ext/ subdirectory.
928
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929By default, Configure will offer to build every extension which appears
930to be supported. For example, Configure will offer to build GDBM_File
7df75831 931only if it is able to find the gdbm library.
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932
933To disable certain extensions so that they are not built, use the
934-Dnoextensions=... and -Donlyextensions=... options. They both accept
935a space-separated list of extensions. The extensions listed in
936C<noextensions> are removed from the list of extensions to build, while
937the C<onlyextensions> is rather more severe and builds only the listed
938extensions. The latter should be used with extreme caution since
939certain extensions are used by many other extensions and modules:
940examples of such modules include Fcntl and IO. The order of processing
941these options is first C<only> (if present), then C<no> (if present).
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942
943Of course, you may always run Configure interactively and select only
944the extensions you want.
945
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946If you unpack any additional extensions in the ext/ directory before
947running Configure, then Configure will offer to build those additional
948extensions as well. Most users probably shouldn't have to do this --
949it is usually easier to build additional extensions later after perl
950has been installed. However, if you wish to have those additional
951extensions statically linked into the perl binary, then this offers a
952convenient way to do that in one step. (It is not necessary, however;
953you can build and install extensions just fine even if you don't have
954dynamic loading. See lib/ExtUtils/MakeMaker.pm for more details.)
955Another way of specifying extra modules is described in
956L<"Adding extra modules to the build"> below.
8d74ce1c 957
dd3196cd 958If you re-use an old config.sh but change your system (e.g. by
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959adding libgdbm) Configure will still offer your old choices of extensions
960for the default answer, but it will also point out the discrepancy to
961you.
962
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963=head2 Including locally-installed libraries
964
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965Perl comes with interfaces to number of libraries, including threads,
966dbm, ndbm, gdbm, and Berkeley db. For the *db* extension, if
8d74ce1c 967Configure can find the appropriate header files and libraries, it will
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968automatically include that extension. The threading extension needs
969to be specified explicitely (see L<Threads>).
970
971Those libraries are not distributed with perl. If your header (.h) files
972for those libraries are not in a directory normally searched by your C
973compiler, then you will need to include the appropriate -I/your/directory
974option when prompted by Configure. If your libraries are not in a
975directory normally searched by your C compiler and linker, then you will
976need to include the appropriate -L/your/directory option when prompted
977by Configure. See the examples below.
8d74ce1c 978
ce80d64e 979=head3 Examples
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980
981=over 4
982
983=item gdbm in /usr/local
984
985Suppose you have gdbm and want Configure to find it and build the
d6baa268 986GDBM_File extension. This example assumes you have gdbm.h
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987installed in /usr/local/include/gdbm.h and libgdbm.a installed in
988/usr/local/lib/libgdbm.a. Configure should figure all the
989necessary steps out automatically.
990
991Specifically, when Configure prompts you for flags for
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992your C compiler, you should include -I/usr/local/include, if it's
993not here yet. Similarly, when Configure prompts you for linker flags,
994you should include -L/usr/local/lib.
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995
996If you are using dynamic loading, then when Configure prompts you for
997linker flags for dynamic loading, you should again include
998-L/usr/local/lib.
999
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1000Again, this should all happen automatically. This should also work if
1001you have gdbm installed in any of (/usr/local, /opt/local, /usr/gnu,
1002/opt/gnu, /usr/GNU, or /opt/GNU).
8d74ce1c 1003
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1004=item BerkeleyDB in /usr/local/BerkeleyDB
1005
1006The version of BerkeleyDB distributed by sleepycat.com installs in a
1007version-specific directory by default, typically something like
1008/usr/local/BerkeleyDB.4.7. To have Configure find that, you need to add
1009-I/usr/local/BerkeleyDB.4.7/include to cc flags, as in the previous example,
1010and you will also have to take extra steps to help Configure find -ldb.
1011Specifically, when Configure prompts you for library directories,
1012add /usr/local/BerkeleyDB.4.7/lib to the list. Also, you will need to
1013add appropriate linker flags to tell the runtime linker where to find the
1014BerkeleyDB shared libraries.
1015
1016It is possible to specify this from the command line (all on one
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1017line):
1018
7df75831 1019 sh Configure -de \
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1020 -Dlocincpth='/usr/local/BerkeleyDB.4.7/include /usr/local/include' \
1021 -Dloclibpth='/usr/local/BerkeleyDB.4.7/lib /usr/local/lib' \
1022 -Aldflags='-R/usr/local/BerkeleyDB.4.7/lib'
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1023
1024locincpth is a space-separated list of include directories to search.
1025Configure will automatically add the appropriate -I directives.
1026
1027loclibpth is a space-separated list of library directories to search.
e8b9ce60 1028Configure will automatically add the appropriate -L directives.
8d74ce1c 1029
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1030The addition to ldflags is so that the dynamic linker knows where to find
1031the BerkeleyDB libraries. For Linux and Solaris, the -R option does that.
1032Other systems may use different flags. Use the appropriate flag for your
1033system.
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1034
1035=back
1036
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1037=head2 Overriding an old config.sh
1038
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1039If you want to use an old config.sh produced by a previous run of
1040Configure, but override some of the items with command line options, you
1041need to use B<Configure -O>.
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1042
1043=head2 GNU-style configure
1044
1045If you prefer the GNU-style configure command line interface, you can
1046use the supplied configure.gnu command, e.g.
1047
1048 CC=gcc ./configure.gnu
1049
1050The configure.gnu script emulates a few of the more common configure
1051options. Try
1052
1053 ./configure.gnu --help
1054
1055for a listing.
1056
1057(The file is called configure.gnu to avoid problems on systems
1058that would not distinguish the files "Configure" and "configure".)
1059
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1060=head2 Malloc Issues
1061
1062Perl relies heavily on malloc(3) to grow data structures as needed,
1063so perl's performance can be noticeably affected by the performance of
1064the malloc function on your system. The perl source is shipped with a
1065version of malloc that has been optimized for the typical requests from
1066perl, so there's a chance that it may be both faster and use less memory
1067than your system malloc.
1068
1069However, if your system already has an excellent malloc, or if you are
1070experiencing difficulties with extensions that use third-party libraries
1071that call malloc, then you should probably use your system's malloc.
1072(Or, you might wish to explore the malloc flags discussed below.)
1073
1074=over 4
1075
1076=item Using the system malloc
1077
1078To build without perl's malloc, you can use the Configure command
1079
1080 sh Configure -Uusemymalloc
1081
1082or you can answer 'n' at the appropriate interactive Configure prompt.
1083
73d6d1b0
RGS
1084Note that Perl's malloc isn't always used by default; that actually
1085depends on your system. For example, on Linux and FreeBSD (and many more
1086systems), Configure chooses to use the system's malloc by default.
1087See the appropriate file in the F<hints/> directory to see how the
1088default is set.
1089
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1090=item -DPERL_POLLUTE_MALLOC
1091
1092NOTE: This flag is enabled automatically on some platforms if you just
7df75831 1093run Configure to accept all the defaults.
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1094
1095Perl's malloc family of functions are normally called Perl_malloc(),
1096Perl_realloc(), Perl_calloc() and Perl_mfree().
1097These names do not clash with the system versions of these functions.
1098
1099If this flag is enabled, however, Perl's malloc family of functions
1100will have the same names as the system versions. This may be required
1101sometimes if you have libraries that like to free() data that may have
1102been allocated by Perl_malloc() and vice versa.
1103
1104Note that enabling this option may sometimes lead to duplicate symbols
1105from the linker for malloc et al. In such cases, the system probably
1106does not allow its malloc functions to be fully replaced with custom
1107versions.
1108
1109=item -DPERL_DEBUGGING_MSTATS
1110
1111This flag enables debugging mstats, which is required to use the
1112Devel::Peek::mstat() function. You cannot enable this unless you are
1113using Perl's malloc, so a typical Configure command would be
1114
7df75831 1115 sh Configure -Accflags=-DPERL_DEBUGGING_MSTATS -Dusemymalloc
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1116
1117to enable this option.
1118
1119=back
1120
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1121=head2 What if it doesn't work?
1122
8d74ce1c 1123If you run into problems, try some of the following ideas.
ff52061e 1124If none of them help, then see L<"Reporting Problems"> below.
8d74ce1c 1125
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1126=over 4
1127
25f94b33
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1128=item Running Configure Interactively
1129
1130If Configure runs into trouble, remember that you can always run
1131Configure interactively so that you can check (and correct) its
1132guesses.
1133
1134All the installation questions have been moved to the top, so you don't
aa689395 1135have to wait for them. Once you've handled them (and your C compiler and
1ec51d55 1136flags) you can type &-d at the next Configure prompt and Configure
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1137will use the defaults from then on.
1138
1139If you find yourself trying obscure command line incantations and
1140config.over tricks, I recommend you run Configure interactively
1141instead. You'll probably save yourself time in the long run.
1142
aa689395 1143=item Hint files
8e07c86e 1144
a0a8d9d3
DD
1145Hint files tell Configure about a number of things:
1146
1147=over 4
1148
1149=item o
1150
1151The peculiarities or conventions of particular platforms -- non-standard
1152library locations and names, default installation locations for binaries,
1153and so on.
1154
1155=item o
1156
1157The deficiencies of the platform -- for example, library functions that,
1158although present, are too badly broken to be usable; or limits on
1159resources that are generously available on most platforms.
1160
1161=item o
1162
1163How best to optimize for the platform, both in terms of binary size and/or
1164speed, and for Perl feature support. Because of wide variations in the
1165implementation of shared libraries and of threading, for example, Configure
1166often needs hints in order to be able to use these features.
1167
1168=back
1169
1170The perl distribution includes many system-specific hints files
1171in the hints/ directory. If one of them matches your system, Configure
1172will offer to use that hint file. Unless you have a very good reason
1173not to, you should accept its offer.
8e07c86e
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1174
1175Several of the hint files contain additional important information.
f5b3b617
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1176If you have any problems, it is a good idea to read the relevant hint file
1177for further information. See hints/solaris_2.sh for an extensive example.
1178More information about writing good hints is in the hints/README.hints
a0a8d9d3
DD
1179file, which also explains hint files known as callback-units.
1180
1181Note that any hint file is read before any Policy file, meaning that
1182Policy overrides hints -- see L</Site-wide Policy settings>.
8e07c86e 1183
73d6d1b0 1184=item WHOA THERE!!!
edb1cbcb 1185
82c11e95
RGS
1186If you are re-using an old config.sh, it's possible that Configure detects
1187different values from the ones specified in this file. You will almost
1188always want to keep the previous value, unless you have changed something
1189on your system.
edb1cbcb
PP
1190
1191For example, suppose you have added libgdbm.a to your system
1192and you decide to reconfigure perl to use GDBM_File. When you run
1193Configure again, you will need to add -lgdbm to the list of libraries.
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1194Now, Configure will find your gdbm include file and library and will
1195issue a message:
edb1cbcb
PP
1196
1197 *** WHOA THERE!!! ***
1198 The previous value for $i_gdbm on this machine was "undef"!
1199 Keep the previous value? [y]
1200
1ec51d55 1201In this case, you do not want to keep the previous value, so you
c3edaffb 1202should answer 'n'. (You'll also have to manually add GDBM_File to
edb1cbcb
PP
1203the list of dynamic extensions to build.)
1204
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1205=item Changing Compilers
1206
1207If you change compilers or make other significant changes, you should
1ec51d55 1208probably not re-use your old config.sh. Simply remove it or
dd3196cd 1209rename it, then rerun Configure with the options you want to use.
8e07c86e 1210
c3edaffb 1211=item Propagating your changes to config.sh
8e07c86e 1212
1ec51d55
CS
1213If you make any changes to config.sh, you should propagate
1214them to all the .SH files by running
1215
1216 sh Configure -S
1217
1218You will then have to rebuild by running
9d67150a
PP
1219
1220 make depend
1221 make
8e07c86e 1222
48370efc
JH
1223=item config.over and config.arch
1224
1225You can also supply a shell script config.over to over-ride
1226Configure's guesses. It will get loaded up at the very end, just
1227before config.sh is created. You have to be careful with this,
1228however, as Configure does no checking that your changes make sense.
1229This file is usually good for site-specific customizations.
1230
1231There is also another file that, if it exists, is loaded before the
1232config.over, called config.arch. This file is intended to be per
1233architecture, not per site, and usually it's the architecture-specific
1234hints file that creates the config.arch.
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1235
1236=item config.h
1237
1ec51d55
CS
1238Many of the system dependencies are contained in config.h.
1239Configure builds config.h by running the config_h.SH script.
1240The values for the variables are taken from config.sh.
8e07c86e 1241
1ec51d55
CS
1242If there are any problems, you can edit config.h directly. Beware,
1243though, that the next time you run Configure, your changes will be
8e07c86e
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1244lost.
1245
1246=item cflags
1247
1248If you have any additional changes to make to the C compiler command
1ec51d55
CS
1249line, they can be made in cflags.SH. For instance, to turn off the
1250optimizer on toke.c, find the line in the switch structure for
1251toke.c and put the command optimize='-g' before the ;; . You
1252can also edit cflags directly, but beware that your changes will be
1253lost the next time you run Configure.
8e07c86e 1254
f5b3b617
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1255To explore various ways of changing ccflags from within a hint file,
1256see the file hints/README.hints.
1257
1258To change the C flags for all the files, edit config.sh and change either
1259$ccflags or $optimize, and then re-run
1ec51d55
CS
1260
1261 sh Configure -S
1262 make depend
8e07c86e 1263
aa689395 1264=item No sh
8e07c86e 1265
c42e3e15
GS
1266If you don't have sh, you'll have to copy the sample file
1267Porting/config.sh to config.sh and edit your config.sh to reflect your
1268system's peculiarities. See Porting/pumpkin.pod for more information.
8e07c86e
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1269You'll probably also have to extensively modify the extension building
1270mechanism.
1271
c3edaffb
PP
1272=item Porting information
1273
e6f03d26 1274Specific information for the OS/2, Plan 9, VMS and Win32 ports is in the
1ec51d55
CS
1275corresponding README files and subdirectories. Additional information,
1276including a glossary of all those config.sh variables, is in the Porting
ce80d64e 1277subdirectory. Porting/Glossary should especially come in handy.
c3edaffb 1278
7f678428 1279Ports for other systems may also be available. You should check out
468f45d5 1280http://www.cpan.org/ports for current information on ports to
7f678428
PP
1281various other operating systems.
1282
ce80d64e 1283If you plan to port Perl to a new architecture, study carefully the
491517e0
JA
1284section titled "Philosophical Issues in Patching and Porting Perl"
1285in the file Porting/pumpkin.pod and the file Porting/patching.pod.
1286Study also how other non-UNIX ports have solved problems.
1287
8e07c86e
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1288=back
1289
ce80d64e 1290=head2 Adding extra modules to the build
fadf0ef5
JH
1291
1292You can specify extra modules or module bundles to be fetched from the
1293CPAN and installed as part of the Perl build. Either use the -Dextras=...
1294command line parameter to Configure, for example like this:
1295
d3df0cfd 1296 Configure -Dextras="Bundle::LWP DBI"
fadf0ef5
JH
1297
1298or answer first 'y' to the question 'Install any extra modules?' and
d3df0cfd 1299then answer "Bundle::LWP DBI" to the 'Extras?' question.
fadf0ef5 1300The module or the bundle names are as for the CPAN module 'install' command.
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1301This will only work if those modules are to be built as dynamic
1302extensions. If you wish to include those extra modules as static
1303extensions, see L<"Extensions"> above.
fadf0ef5
JH
1304
1305Notice that because the CPAN module will be used to fetch the extra
1306modules, you will need access to the CPAN, either via the Internet,
1307or via a local copy such as a CD-ROM or a local CPAN mirror. If you
1308do not, using the extra modules option will die horribly.
1309
1310Also notice that you yourself are responsible for satisfying any extra
1311dependencies such as external headers or libraries BEFORE trying the build.
d3df0cfd 1312For example: you will need to have the Foo database specific
fadf0ef5
JH
1313headers and libraries installed for the DBD::Foo module. The Configure
1314process or the Perl build process will not help you with these.
1315
ce80d64e 1316=head2 suidperl
03739d21 1317
ce80d64e
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1318suidperl is an optional component, which is normally neither built
1319nor installed by default. From perlfaq1:
03739d21
JH
1320
1321 On some systems, setuid and setgid scripts (scripts written
1322 in the C shell, Bourne shell, or Perl, for example, with the
1323 set user or group ID permissions enabled) are insecure due to
1324 a race condition in the kernel. For those systems, Perl versions
1325 5 and 4 attempt to work around this vulnerability with an optional
1326 component, a special program named suidperl, also known as sperl.
1327 This program attempts to emulate the set-user-ID and set-group-ID
1328 features of the kernel.
1329
1330Because of the buggy history of suidperl, and the difficulty
1331of properly security auditing as large and complex piece of
1332software as Perl, we cannot recommend using suidperl and the feature
1333should be considered deprecated.
08854360 1334
ce80d64e 1335Instead, use a tool specifically designed to handle changes in
08854360 1336privileges, such as B<sudo>.
03739d21 1337
8e07c86e
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1338=head1 make depend
1339
bfb7748a
AD
1340This will look for all the includes. The output is stored in makefile.
1341The only difference between Makefile and makefile is the dependencies at
1342the bottom of makefile. If you have to make any changes, you should edit
ce80d64e 1343makefile, not Makefile, since the Unix make command reads makefile first.
bfb7748a
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1344(On non-Unix systems, the output may be stored in a different file.
1345Check the value of $firstmakefile in your config.sh if in doubt.)
8e07c86e
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1346
1347Configure will offer to do this step for you, so it isn't listed
1348explicitly above.
1349
1350=head1 make
1351
1352This will attempt to make perl in the current directory.
1353
8d410bc4
YST
1354=head2 Expected errors
1355
f5b5f377 1356These error reports are normal, and can be ignored:
8d410bc4
YST
1357
1358 ...
1359 make: [extra.pods] Error 1 (ignored)
1360 ...
1361 make: [extras.make] Error 1 (ignored)
1362
8d74ce1c
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1363=head2 What if it doesn't work?
1364
8e07c86e 1365If you can't compile successfully, try some of the following ideas.
7f678428 1366If none of them help, and careful reading of the error message and
8d74ce1c 1367the relevant manual pages on your system doesn't help,
ff52061e 1368then see L<"Reporting Problems"> below.
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1369
1370=over 4
1371
1ec51d55 1372=item hints
8e07c86e
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1373
1374If you used a hint file, try reading the comments in the hint file
1375for further tips and information.
1376
1ec51d55 1377=item extensions
8e07c86e 1378
1ec51d55 1379If you can successfully build miniperl, but the process crashes
ce80d64e 1380during the building of extensions, run
c3edaffb 1381
3a6175e1 1382 make minitest
c3edaffb
PP
1383
1384to test your version of miniperl.
1385
e57fd563
PP
1386=item locale
1387
bfb7748a
AD
1388If you have any locale-related environment variables set, try unsetting
1389them. I have some reports that some versions of IRIX hang while
1390running B<./miniperl configpm> with locales other than the C locale.
1391See the discussion under L<"make test"> below about locales and the
08854360 1392whole L<perllocale/"LOCALE PROBLEMS"> section in the file pod/perllocale.pod.
3e6e419a
JH
1393The latter is especially useful if you see something like this
1394
1395 perl: warning: Setting locale failed.
1396 perl: warning: Please check that your locale settings:
1397 LC_ALL = "En_US",
1398 LANG = (unset)
1399 are supported and installed on your system.
1400 perl: warning: Falling back to the standard locale ("C").
1401
1402at Perl startup.
e57fd563 1403
06aa495b
DM
1404=item other environment variables
1405
1406Configure does not check for environment variables that can sometimes
1407have a major influence on how perl is built or tested. For example,
1408OBJECT_MODE on AIX determines the way the compiler and linker deal with
1409their objects, but this is a variable that only influences build-time
1410behaviour, and should not affect the perl scripts that are eventually
1411executed by the perl binary. Other variables, like PERL_UNICODE,
adbb55c0 1412PERL5LIB, and PERL5OPT will influence the behaviour of the test suite.
06aa495b
DM
1413So if you are getting strange test failures, you may want to try
1414retesting with the various PERL variables unset.
1415
7f678428 1416=item varargs
c3edaffb
PP
1417
1418If you get varargs problems with gcc, be sure that gcc is installed
bfb7748a
AD
1419correctly and that you are not passing -I/usr/include to gcc. When using
1420gcc, you should probably have i_stdarg='define' and i_varargs='undef'
ce80d64e 1421in config.sh. The problem is usually solved by installing gcc
bfb7748a
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1422correctly. If you do change config.sh, don't forget to propagate
1423your changes (see L<"Propagating your changes to config.sh"> below).
7f678428 1424See also the L<"vsprintf"> item below.
c3edaffb 1425
bfb7748a 1426=item util.c
c3edaffb
PP
1427
1428If you get error messages such as the following (the exact line
bfb7748a 1429numbers and function name may vary in different versions of perl):
c3edaffb 1430
bfb7748a
AD
1431 util.c: In function `Perl_form':
1432 util.c:1107: number of arguments doesn't match prototype
1433 proto.h:125: prototype declaration
c3edaffb
PP
1434
1435it might well be a symptom of the gcc "varargs problem". See the
7f678428 1436previous L<"varargs"> item.
c3edaffb 1437
1ec51d55 1438=item LD_LIBRARY_PATH
c3edaffb
PP
1439
1440If you run into dynamic loading problems, check your setting of
aa689395
PP
1441the LD_LIBRARY_PATH environment variable. If you're creating a static
1442Perl library (libperl.a rather than libperl.so) it should build
c3edaffb
PP
1443fine with LD_LIBRARY_PATH unset, though that may depend on details
1444of your local set-up.
1445
aa689395 1446=item nm extraction
c3edaffb
PP
1447
1448If Configure seems to be having trouble finding library functions,
1449try not using nm extraction. You can do this from the command line
1450with
1451
1452 sh Configure -Uusenm
1453
1454or by answering the nm extraction question interactively.
1ec51d55 1455If you have previously run Configure, you should not reuse your old
c3edaffb
PP
1456config.sh.
1457
bfb7748a
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1458=item umask not found
1459
1460If the build processes encounters errors relating to umask(), the problem
1461is probably that Configure couldn't find your umask() system call.
1462Check your config.sh. You should have d_umask='define'. If you don't,
1463this is probably the L<"nm extraction"> problem discussed above. Also,
1464try reading the hints file for your system for further information.
1465
7f678428 1466=item vsprintf
c3edaffb
PP
1467
1468If you run into problems with vsprintf in compiling util.c, the
1469problem is probably that Configure failed to detect your system's
1470version of vsprintf(). Check whether your system has vprintf().
1471(Virtually all modern Unix systems do.) Then, check the variable
1472d_vprintf in config.sh. If your system has vprintf, it should be:
1473
1474 d_vprintf='define'
1475
1476If Configure guessed wrong, it is likely that Configure guessed wrong
bfb7748a
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1477on a number of other common functions too. This is probably
1478the L<"nm extraction"> problem discussed above.
c3edaffb 1479
3fe9a6f1
PP
1480=item do_aspawn
1481
1482If you run into problems relating to do_aspawn or do_spawn, the
1483problem is probably that Configure failed to detect your system's
bfb7748a
AD
1484fork() function. Follow the procedure in the previous item
1485on L<"nm extraction">.
3fe9a6f1 1486
84902520
TB
1487=item __inet_* errors
1488
1489If you receive unresolved symbol errors during Perl build and/or test
1490referring to __inet_* symbols, check to see whether BIND 8.1 is
1491installed. It installs a /usr/local/include/arpa/inet.h that refers to
1492these symbols. Versions of BIND later than 8.1 do not install inet.h
1493in that location and avoid the errors. You should probably update to a
6d240721
JH
1494newer version of BIND (and remove the files the old one left behind).
1495If you can't, you can either link with the updated resolver library provided
1496with BIND 8.1 or rename /usr/local/bin/arpa/inet.h during the Perl build and
1497test process to avoid the problem.
1498
73d6d1b0 1499=item .*_r() prototype NOT found
6d240721
JH
1500
1501On a related note, if you see a bunch of complaints like the above about
1502reentrant functions - specifically networking-related ones - being present
1503but without prototypes available, check to see if BIND 8.1 (or possibly
1504other BIND 8 versions) is (or has been) installed. They install
1505header files such as netdb.h into places such as /usr/local/include (or into
1506another directory as specified at build/install time), at least optionally.
f1300be0 1507Remove them or put them in someplace that isn't in the C preprocessor's
6d240721
JH
1508header file include search path (determined by -I options plus defaults,
1509normally /usr/include).
84902520 1510
d6baa268
JH
1511=item #error "No DATAMODEL_NATIVE specified"
1512
1513This is a common error when trying to build perl on Solaris 2.6 with a
1514gcc installation from Solaris 2.5 or 2.5.1. The Solaris header files
1515changed, so you need to update your gcc installation. You can either
1516rerun the fixincludes script from gcc or take the opportunity to
1517update your gcc installation.
1518
aa689395 1519=item Optimizer
c3edaffb 1520
9d67150a 1521If you can't compile successfully, try turning off your compiler's
aa689395 1522optimizer. Edit config.sh and change the line
9d67150a
PP
1523
1524 optimize='-O'
1525
bfb7748a 1526to
9d67150a
PP
1527
1528 optimize=' '
1529
1530then propagate your changes with B<sh Configure -S> and rebuild
1531with B<make depend; make>.
1532
4bbc1586 1533=item Missing functions and Undefined symbols
9d67150a 1534
4bbc1586
AD
1535If the build of miniperl fails with a long list of missing functions or
1536undefined symbols, check the libs variable in the config.sh file. It
1537should look something like
1538
1539 libs='-lsocket -lnsl -ldl -lm -lc'
1540
1541The exact libraries will vary from system to system, but you typically
1542need to include at least the math library -lm. Normally, Configure
1543will suggest the correct defaults. If the libs variable is empty, you
1544need to start all over again. Run
1545
1546 make distclean
1547
1548and start from the very beginning. This time, unless you are sure of
1549what you are doing, accept the default list of libraries suggested by
1550Configure.
1551
1552If the libs variable looks correct, you might have the
1553L<"nm extraction"> problem discussed above.
1554
1555If you stil have missing routines or undefined symbols, you probably
1556need to add some library or other, or you need to undefine some feature
1557that Configure thought was there but is defective or incomplete. If
1558you used a hint file, see if it has any relevant advice. You can also
1559look through through config.h for likely suspects.
8e07c86e 1560
1ec51d55 1561=item toke.c
8e07c86e 1562
1ec51d55
CS
1563Some compilers will not compile or optimize the larger files (such as
1564toke.c) without some extra switches to use larger jump offsets or
1565allocate larger internal tables. You can customize the switches for
1566each file in cflags. It's okay to insert rules for specific files into
1567makefile since a default rule only takes effect in the absence of a
8e07c86e
AD
1568specific rule.
1569
7f678428 1570=item Missing dbmclose
8e07c86e 1571
c3edaffb
PP
1572SCO prior to 3.2.4 may be missing dbmclose(). An upgrade to 3.2.4
1573that includes libdbm.nfs (which includes dbmclose()) may be available.
8e07c86e 1574
f3d9a6ba 1575=item Note (probably harmless): No library found for -lsomething
7f678428
PP
1576
1577If you see such a message during the building of an extension, but
1578the extension passes its tests anyway (see L<"make test"> below),
1579then don't worry about the warning message. The extension
1580Makefile.PL goes looking for various libraries needed on various
aa689395 1581systems; few systems will need all the possible libraries listed.
74b7c41f
AD
1582Most users will see warnings for the ones they don't have. The
1583phrase 'probably harmless' is intended to reassure you that nothing
1584unusual is happening, and the build process is continuing.
7f678428
PP
1585
1586On the other hand, if you are building GDBM_File and you get the
1587message
1588
f3d9a6ba 1589 Note (probably harmless): No library found for -lgdbm
7f678428
PP
1590
1591then it's likely you're going to run into trouble somewhere along
1592the line, since it's hard to see how you can use the GDBM_File
1593extension without the -lgdbm library.
1594
1595It is true that, in principle, Configure could have figured all of
1596this out, but Configure and the extension building process are not
1597quite that tightly coordinated.
1598
aa689395
PP
1599=item sh: ar: not found
1600
1601This is a message from your shell telling you that the command 'ar'
1602was not found. You need to check your PATH environment variable to
1603make sure that it includes the directory with the 'ar' command. This
1ec51d55 1604is a common problem on Solaris, where 'ar' is in the /usr/ccs/bin
aa689395
PP
1605directory.
1606
1607=item db-recno failure on tests 51, 53 and 55
1608
1609Old versions of the DB library (including the DB library which comes
1610with FreeBSD 2.1) had broken handling of recno databases with modified
1611bval settings. Upgrade your DB library or OS.
1612
6087ac44
JH
1613=item Bad arg length for semctl, is XX, should be ZZZ
1614
11906ba0 1615If you get this error message from the ext/IPC/SysV/t/sem test, your System
6087ac44
JH
1616V IPC may be broken. The XX typically is 20, and that is what ZZZ
1617also should be. Consider upgrading your OS, or reconfiguring your OS
1618to include the System V semaphores.
1619
11906ba0 1620=item ext/IPC/SysV/t/sem........semget: No space left on device
220f3621
GS
1621
1622Either your account or the whole system has run out of semaphores. Or
1623both. Either list the semaphores with "ipcs" and remove the unneeded
1624ones (which ones these are depends on your system and applications)
1625with "ipcrm -s SEMAPHORE_ID_HERE" or configure more semaphores to your
1626system.
1627
d6baa268
JH
1628=item GNU binutils
1629
1630If you mix GNU binutils (nm, ld, ar) with equivalent vendor-supplied
1631tools you may be in for some trouble. For example creating archives
1632with an old GNU 'ar' and then using a new current vendor-supplied 'ld'
1633may lead into linking problems. Either recompile your GNU binutils
1634under your current operating system release, or modify your PATH not
1635to include the GNU utils before running Configure, or specify the
1636vendor-supplied utilities explicitly to Configure, for example by
1637Configure -Dar=/bin/ar.
1638
16dc217a
GS
1639=item THIS PACKAGE SEEMS TO BE INCOMPLETE
1640
1641The F<Configure> program has not been able to find all the files which
1642make up the complete Perl distribution. You may have a damaged source
1643archive file (in which case you may also have seen messages such as
1644C<gzip: stdin: unexpected end of file> and C<tar: Unexpected EOF on
1645archive file>), or you may have obtained a structurally-sound but
1646incomplete archive. In either case, try downloading again from the
1647official site named at the start of this document. If you do find
1648that any site is carrying a corrupted or incomplete source code
1649archive, please report it to the site's maintainer.
1650
16dc217a
GS
1651=item invalid token: ##
1652
ce80d64e
AD
1653You are using a non-ANSI-compliant C compiler. To compile Perl, you
1654need to use a compiler that supports ANSI C. If there is a README
1655file for your system, it may have further details on your compiler
1656options.
16dc217a 1657
1ec51d55 1658=item Miscellaneous
8e07c86e 1659
7df75831 1660Some additional things that have been reported:
8e07c86e
AD
1661
1662Genix may need to use libc rather than libc_s, or #undef VARARGS.
1663
1664NCR Tower 32 (OS 2.01.01) may need -W2,-Sl,2000 and #undef MKDIR.
1665
9ede5bc8 1666UTS may need one or more of -K or -g, and undef LSTAT.
8e07c86e 1667
11906ba0 1668FreeBSD can fail the ext/IPC/SysV/t/sem.t test if SysV IPC has not been
5cda700b 1669configured in the kernel. Perl tries to detect this, though, and
ce80d64e 1670you will get a message telling you what to do.
6087ac44 1671
6c8d78fb
HS
1672Building Perl on a system that has also BIND (headers and libraries)
1673installed may run into troubles because BIND installs its own netdb.h
1674and socket.h, which may not agree with the operating system's ideas of
1675the same files. Similarly, including -lbind may conflict with libc's
1676view of the world. You may have to tweak -Dlocincpth and -Dloclibpth
1677to avoid the BIND.
1678
8e07c86e
AD
1679=back
1680
58a21a9b
JH
1681=head2 Cross-compilation
1682
e7a3c61b
JH
1683Perl can be cross-compiled. It is just not trivial, cross-compilation
1684rarely is. Perl is routinely cross-compiled for many platforms (as of
1685June 2005 at least PocketPC aka WinCE, Open Zaurus, EPOC, Symbian, and
1686the IBM OS/400). These platforms are known as the B<target> platforms,
1687while the systems where the compilation takes place are the B<host>
1688platforms.
1689
1690What makes the situation difficult is that first of all,
1691cross-compilation environments vary significantly in how they are set
1692up and used, and secondly because the primary way of configuring Perl
1693(using the rather large Unix-tool-dependent Configure script) is not
1694awfully well suited for cross-compilation. However, starting from
1695version 5.8.0, the Configure script also knows one way of supporting
1696cross-compilation support, please keep reading.
1697
1698See the following files for more information about compiling Perl for
1699the particular platforms:
1700
1701=over 4
1702
1703=item WinCE/PocketPC
1704
75472953 1705README.ce
e7a3c61b
JH
1706
1707=item Open Zaurus
1708
1709Cross/README
1710
1711=item EPOC
1712
1713README.epoc
1714
1715=item Symbian
1716
1717README.symbian
1718
1719=item OS/400
1720
1721README.os400
1722
1723=back
1724
1725Packaging and transferring either the core Perl modules or CPAN
1726modules to the target platform is also left up to the each
1727cross-compilation environment. Often the cross-compilation target
1728platforms are somewhat limited in diskspace: see the section
1729L<Minimizing the Perl installation> to learn more of the minimal set
1730of files required for a functional Perl installation.
1731
1732For some cross-compilation environments the Configure option
1733C<-Dinstallprefix=...> might be handy, see L<Changing the installation
1734directory>.
1735
1736About the cross-compilation support of Configure: what is known to
1737work is running Configure in a cross-compilation environment and
1738building the miniperl executable. What is known not to work is
1739building the perl executable because that would require building
1740extensions: Dynaloader statically and File::Glob dynamically, for
1741extensions one needs MakeMaker and MakeMaker is not yet
1742cross-compilation aware, and neither is the main Makefile.
1743
1744The cross-compilation setup of Configure has successfully been used in
1745at least two Linux cross-compilation environments. The setups were
1746both such that the host system was Intel Linux with a gcc built for
1747cross-compiling into ARM Linux, and there was a SSH connection to the
1748target system.
1749
1750To run Configure in cross-compilation mode the basic switch that
1751has to be used is C<-Dusecrosscompile>.
58a21a9b
JH
1752
1753 sh ./Configure -des -Dusecrosscompile -D...
1754
1755This will make the cpp symbol USE_CROSS_COMPILE and the %Config
b0f06652
VK
1756symbol C<usecrosscompile> available, and C<xconfig.h> will be used
1757for cross-compilation.
58a21a9b
JH
1758
1759During the Configure and build, certain helper scripts will be created
1760into the Cross/ subdirectory. The scripts are used to execute a
1761cross-compiled executable, and to transfer files to and from the
1762target host. The execution scripts are named F<run-*> and the
1763transfer scripts F<to-*> and F<from-*>. The part after the dash is
1764the method to use for remote execution and transfer: by default the
1765methods are B<ssh> and B<scp>, thus making the scripts F<run-ssh>,
1766F<to-scp>, and F<from-scp>.
1767
1768To configure the scripts for a target host and a directory (in which
1769the execution will happen and which is to and from where the transfer
1770happens), supply Configure with
1771
1772 -Dtargethost=so.me.ho.st -Dtargetdir=/tar/get/dir
1773
1774The targethost is what e.g. ssh will use as the hostname, the targetdir
93bc48fa
JH
1775must exist (the scripts won't create it), the targetdir defaults to /tmp.
1776You can also specify a username to use for ssh/rsh logins
58a21a9b
JH
1777
1778 -Dtargetuser=luser
1779
1780but in case you don't, "root" will be used.
1781
93bc48fa
JH
1782Because this is a cross-compilation effort, you will also need to specify
1783which target environment and which compilation environment to use.
1784This includes the compiler, the header files, and the libraries.
1785In the below we use the usual settings for the iPAQ cross-compilation
1786environment:
58a21a9b
JH
1787
1788 -Dtargetarch=arm-linux
1789 -Dcc=arm-linux-gcc
1790 -Dusrinc=/skiff/local/arm-linux/include
1791 -Dincpth=/skiff/local/arm-linux/include
1792 -Dlibpth=/skiff/local/arm-linux/lib
1793
1794If the name of the C<cc> has the usual GNU C semantics for cross
1795compilers, that is, CPU-OS-gcc, the names of the C<ar>, C<nm>, and
1796C<ranlib> will also be automatically chosen to be CPU-OS-ar and so on.
93bc48fa
JH
1797(The C<ld> requires more thought and will be chosen later by Configure
1798as appropriate.) Also, in this case the incpth, libpth, and usrinc
1799will be guessed by Configure (unless explicitly set to something else,
1800in which case Configure's guesses with be appended).
58a21a9b
JH
1801
1802In addition to the default execution/transfer methods you can also
1803choose B<rsh> for execution, and B<rcp> or B<cp> for transfer,
1804for example:
1805
1806 -Dtargetrun=rsh -Dtargetto=rcp -Dtargetfrom=cp
1807
1808Putting it all together:
1809
1810 sh ./Configure -des -Dusecrosscompile \
93bc48fa
JH
1811 -Dtargethost=so.me.ho.st \
1812 -Dtargetdir=/tar/get/dir \
58a21a9b
JH
1813 -Dtargetuser=root \
1814 -Dtargetarch=arm-linux \
1815 -Dcc=arm-linux-gcc \
1816 -Dusrinc=/skiff/local/arm-linux/include \
1817 -Dincpth=/skiff/local/arm-linux/include \
1818 -Dlibpth=/skiff/local/arm-linux/lib \
1819 -D...
1820
e7a3c61b 1821or if you are happy with the defaults:
93bc48fa
JH
1822
1823 sh ./Configure -des -Dusecrosscompile \
1824 -Dtargethost=so.me.ho.st \
1825 -Dcc=arm-linux-gcc \
1826 -D...
1827
e7a3c61b
JH
1828Another example where the cross-compiler has been installed under
1829F</usr/local/arm/2.95.5>:
1830
1831 sh ./Configure -des -Dusecrosscompile \
1832 -Dtargethost=so.me.ho.st \
1833 -Dcc=/usr/local/arm/2.95.5/bin/arm-linux-gcc \
1834 -Dincpth=/usr/local/arm/2.95.5/include \
1835 -Dusrinc=/usr/local/arm/2.95.5/include \
1836 -Dlibpth=/usr/local/arm/2.95.5/lib
1837
8e07c86e
AD
1838=head1 make test
1839
d6baa268
JH
1840This will run the regression tests on the perl you just made. If
1841'make test' doesn't say "All tests successful" then something went
1842wrong. See the file t/README in the t subdirectory.
84902520 1843
84902520 1844Note that you can't run the tests in background if this disables
fb73857a
PP
1845opening of /dev/tty. You can use 'make test-notty' in that case but
1846a few tty tests will be skipped.
c3edaffb 1847
c4f23d77
AD
1848=head2 What if make test doesn't work?
1849
1ec51d55
CS
1850If make test bombs out, just cd to the t directory and run ./TEST
1851by hand to see if it makes any difference. If individual tests
c3edaffb 1852bomb, you can run them by hand, e.g.,
8e07c86e 1853
785aa5e3 1854 cd t ; ./perl -MTestInit op/groups.t
8e07c86e 1855
aa689395 1856Another way to get more detailed information about failed tests and
1ec51d55 1857individual subtests is to cd to the t directory and run
aa689395 1858
785aa5e3 1859 cd t ; ./perl harness <list of tests>
aa689395 1860
fb73857a 1861(this assumes that most basic tests succeed, since harness uses
785aa5e3
RGS
1862complicated constructs). If no list of tests is provided, harness
1863will run all tests.
10c7e831 1864
fb73857a 1865You should also read the individual tests to see if there are any helpful
10c7e831
JH
1866comments that apply to your system. You may also need to setup your
1867shared library path if you get errors like:
1868
1869 /sbin/loader: Fatal Error: cannot map libperl.so
1870
1871See L</"Building a shared Perl library"> earlier in this document.
c3edaffb 1872
c4f23d77
AD
1873=over 4
1874
1875=item locale
1876
1ec51d55 1877Note: One possible reason for errors is that some external programs
c07a80fd 1878may be broken due to the combination of your environment and the way
785aa5e3 1879'make test' exercises them. For example, this may happen if you have
1ec51d55
CS
1880one or more of these environment variables set: LC_ALL LC_CTYPE
1881LC_COLLATE LANG. In some versions of UNIX, the non-English locales
e57fd563
PP
1882are known to cause programs to exhibit mysterious errors.
1883
1884If you have any of the above environment variables set, please try
aa689395
PP
1885
1886 setenv LC_ALL C
1887
1888(for C shell) or
1889
1890 LC_ALL=C;export LC_ALL
1891
1ec51d55
CS
1892for Bourne or Korn shell) from the command line and then retry
1893make test. If the tests then succeed, you may have a broken program that
aa689395 1894is confusing the testing. Please run the troublesome test by hand as
e57fd563 1895shown above and see whether you can locate the program. Look for
1ec51d55
CS
1896things like: exec, `backquoted command`, system, open("|...") or
1897open("...|"). All these mean that Perl is trying to run some
e57fd563 1898external program.
eed2e782 1899
0740bb5b
AD
1900=item Timing problems
1901
c29923ff
JH
1902Several tests in the test suite check timing functions, such as
1903sleep(), and see if they return in a reasonable amount of time.
9341413f
JH
1904If your system is quite busy and doesn't respond quickly enough,
1905these tests might fail. If possible, try running the tests again
1906with the system under a lighter load. These timing-sensitive
1907and load-sensitive tests include F<t/op/alarm.t>,
3831a787
NC
1908F<ext/Time-HiRes/t/HiRes.t>, F<ext/threads-shared/t/waithires.t>,
1909F<ext/threads-shared/t/stress.t>, F<lib/Benchmark.t>,
9341413f 1910F<lib/Memoize/t/expmod_t.t>, and F<lib/Memoize/t/speed.t>.
0740bb5b 1911
f89caa8d
RGS
1912You might also experience some failures in F<t/op/stat.t> if you build
1913perl on an NFS filesystem, if the remote clock and the system clock are
1914different.
1915
c4f23d77
AD
1916=item Out of memory
1917
1918On some systems, particularly those with smaller amounts of RAM, some
1919of the tests in t/op/pat.t may fail with an "Out of memory" message.
7970f296
GS
1920For example, on my SparcStation IPC with 12 MB of RAM, in perl5.5.670,
1921test 85 will fail if run under either t/TEST or t/harness.
c4f23d77
AD
1922
1923Try stopping other jobs on the system and then running the test by itself:
1924
785aa5e3 1925 cd t; ./perl -MTestInit op/pat.t
c4f23d77
AD
1926
1927to see if you have any better luck. If your perl still fails this
1928test, it does not necessarily mean you have a broken perl. This test
1929tries to exercise the regular expression subsystem quite thoroughly,
1930and may well be far more demanding than your normal usage.
1931
a55bb48b
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1932=item libgcc_s.so.1: cannot open shared object file
1933
1934This message has been reported on gcc-3.2.3 and earlier installed with
1935a non-standard prefix. Setting the LD_LIBRARY_PATH environment variable
1936(or equivalent) to include gcc's lib/ directory with the libgcc_s.so.1
1937shared library should fix the problem.
1938
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1939=item Failures from lib/File/Temp/t/security saying "system possibly insecure"
1940
1941First, such warnings are not necessarily serious or indicative of a
1942real security threat. That being said, they bear investigating.
1943
1944Note that each of the tests is run twice. The first time is in the
1945directory returned by File::Spec->tmpdir() (often /tmp on Unix
1946systems), and the second time in the directory from which the test was
1947run (usually the 't' directory, if the test was run as part of 'make
1948test').
1949
1950The tests may fail for the following reasons:
1951
1952(1) If the directory the tests are being run in is owned by somebody
1953other than the user running the tests, or by root (uid 0).
1954
1955This failure can happen if the Perl source code distribution is
1956unpacked in such a way that the user ids in the distribution package
1957are used as-is. Some tar programs do this.
1958
1959(2) If the directory the tests are being run in is writable by group or
1960by others, and there is no sticky bit set for the directory. (With
1961UNIX/POSIX semantics, write access to a directory means the right to
1962add or remove files in that directory. The 'sticky bit' is a feature
1963used in some UNIXes to give extra protection to files: if the bit is
1964set for a directory, no one but the owner (or root) can remove that
1965file even if the permissions would otherwise allow file removal by
1966others.)
1967
1968This failure may or may not be a real problem: it depends on the
1969permissions policy used on this particular system. This failure can
1970also happen if the system either doesn't support the sticky bit (this
1971is the case with many non-UNIX platforms: in principle File::Temp
1972should know about these platforms and skip the tests), or if the system
1973supports the sticky bit but for some reason or reasons it is not being
1974used. This is, for example, the case with HP-UX: as of HP-UX release
197511.00, the sticky bit is very much supported, but HP-UX doesn't use it
1976on its /tmp directory as shipped. Also, as with the permissions, some
1977local policy might dictate that the stickiness is not used.
781948c1 1978
b2b23189
JH
1979(3) If the system supports the POSIX 'chown giveaway' feature and if
1980any of the parent directories of the temporary file back to the root
1981directory are 'unsafe', using the definitions given above in (1) and
4f76e5ba
AD
1982(2). For Unix systems, this is usually not an issue if you are
1983building on a local disk. See the documentation for the File::Temp
1984module for more information about 'chown giveaway'.
781948c1
JH
1985
1986See the documentation for the File::Temp module for more information
4f76e5ba 1987about the various security aspects of temporary files.
781948c1 1988
c4f23d77
AD
1989=back
1990
5ee651a9
NC
1991The core distribution can now run its regression tests in parallel on
1992Unix-like platforms. Instead of running C<make test>, set C<TEST_JOBS> in
1993your environment to the number of tests to run in parallel, and run
1994C<make test_harness>. On a Bourne-like shell, this can be done as
1995
1996 TEST_JOBS=3 make test_harness # Run 3 tests in parallel
1997
1998An environment variable is used, rather than parallel make itself, because
1999L<TAP::Harness> needs to be able to schedule individual non-conflicting test
2000scripts itself, and there is no standard interface to C<make> utilities to
2001interact with their job schedulers.
2002
8e07c86e
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2003=head1 make install
2004
2005This will put perl into the public directory you specified to
1ec51d55 2006Configure; by default this is /usr/local/bin. It will also try
8e07c86e 2007to put the man pages in a reasonable place. It will not nroff the man
aa689395 2008pages, however. You may need to be root to run B<make install>. If you
ce80d64e
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2009are not root, you must still have permission to install into the directories
2010in question and you should ignore any messages about chown not working.
2011
2012If "make install" just says "`install' is up to date" or something
2013similar, you may be on a case-insensitive filesystems such as Mac's HFS+,
2014and you should say "make install-all". (This confusion is brought to you
2015by the Perl distribution having a file called INSTALL.)
8e07c86e 2016
dd64f1c3
AD
2017=head2 Installing perl under different names
2018
2019If you want to install perl under a name other than "perl" (for example,
2020when installing perl with special features enabled, such as debugging),
2021indicate the alternate name on the "make install" line, such as:
2022
2023 make install PERLNAME=myperl
2024
beb13193 2025You can separately change the base used for versioned names (like
be8498a1 2026"perl5.8.9") by setting PERLNAME_VERBASE, like
beb13193
RS
2027
2028 make install PERLNAME=perl5 PERLNAME_VERBASE=perl
2029
5cda700b
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2030This can be useful if you have to install perl as "perl5" (e.g. to
2031avoid conflicts with an ancient version in /usr/bin supplied by your vendor).
be8498a1 2032Without this the versioned binary would be called "perl55.8.8".
beb13193 2033
ce80d64e
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2034=head2 Installing perl under a different directory
2035
2036You can install perl under a different destination directory by using
2037the DESTDIR variable during C<make install>, with a command like
2038
2039 make install DESTDIR=/tmp/perl5
2040
2041DESTDIR is automatically prepended to all the installation paths. See
7df75831 2042the example in L<"DESTDIR"> above.
ce80d64e 2043
dd64f1c3
AD
2044=head2 Installed files
2045
8e07c86e
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2046If you want to see exactly what will happen without installing
2047anything, you can run
4633a7c4 2048
8e07c86e
AD
2049 ./perl installperl -n
2050 ./perl installman -n
2051
1ec51d55 2052make install will install the following:
8e07c86e 2053
d56c5707
JH
2054 binaries
2055
8e07c86e 2056 perl,
be8498a1 2057 perl5.n.n where 5.n.n is the current release number. This
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2058 will be a link to perl.
2059 suidperl,
be8498a1 2060 sperl5.n.n If you requested setuid emulation.
8e07c86e 2061 a2p awk-to-perl translator
d56c5707
JH
2062
2063 scripts
2064
73d6d1b0
RGS
2065 cppstdin This is used by the deprecated switch perl -P, if
2066 your cc -E can't read from stdin.
8e07c86e 2067 c2ph, pstruct Scripts for handling C structures in header files.
73d6d1b0
RGS
2068 config_data Manage Module::Build-like module configuration
2069 corelist Shows versions of modules that come with different
2070 versions of perl
2071 cpan The CPAN shell
2072 cpan2dist The CPANPLUS distribution creator
2073 cpanp The CPANPLUS shell
2074 cpanp-run-perl An helper for cpanp
f5b5f377 2075 dprofpp Perl code profiler post-processor
73d6d1b0 2076 enc2xs Encoding module generator
8e07c86e 2077 find2perl find-to-perl translator
aa689395 2078 h2ph Extract constants and simple macros from C headers
8e07c86e 2079 h2xs Converts C .h header files to Perl extensions.
73d6d1b0
RGS
2080 instmodsh A shell to examine installed modules.
2081 libnetcfg Configure libnet.
24b3df7f 2082 perlbug Tool to report bugs in Perl.
8e07c86e 2083 perldoc Tool to read perl's pod documentation.
73d6d1b0
RGS
2084 perlivp Perl Installation Verification Procedure
2085 piconv A Perl implementation of the encoding conversion
2086 utility iconv
aa689395 2087 pl2pm Convert Perl 4 .pl files to Perl 5 .pm modules
8e07c86e 2088 pod2html, Converters from perl's pod documentation format
aa689395 2089 pod2latex, to other useful formats.
d56c5707
JH
2090 pod2man,
2091 pod2text,
d56c5707 2092 pod2usage
73d6d1b0
RGS
2093 podchecker POD syntax checker
2094 podselect Prints sections of POD documentation
2095 prove A command-line tool for running tests
2096 psed A Perl implementation of sed
2097 ptar A Perl implementation of tar
2098 ptardiff A diff for tar archives
2099 s2p sed-to-perl translator
2100 shasum A tool to print or check SHA checksums
aa689395 2101 splain Describe Perl warnings and errors
73d6d1b0 2102 xsubpp Compiler to convert Perl XS code into C code
8e07c86e 2103
d56c5707
JH
2104 library files
2105
2106 in $privlib and $archlib specified to
8e07c86e 2107 Configure, usually under /usr/local/lib/perl5/.
d56c5707
JH
2108
2109 documentation
2110
d6baa268
JH
2111 man pages in $man1dir, usually /usr/local/man/man1.
2112 module man
2113 pages in $man3dir, usually /usr/local/man/man3.
8e07c86e
AD
2114 pod/*.pod in $privlib/pod/.
2115
33cceb07 2116installperl will also create the directories listed above
d6baa268 2117in L<"Installation Directories">.
4633a7c4 2118
d56c5707 2119Perl's *.h header files and the libperl library are also installed
d6baa268 2120under $archlib so that any user may later build new modules, run the
56c6f531
JH
2121optional Perl compiler, or embed the perl interpreter into another
2122program even if the Perl source is no longer available.
8e07c86e 2123
33cceb07
RGS
2124=head2 Installing only version-specific parts
2125
d56c5707
JH
2126Sometimes you only want to install the version-specific parts of the perl
2127installation. For example, you may wish to install a newer version of
33cceb07 2128perl alongside an already installed production version without
d56c5707
JH
2129disabling installation of new modules for the production version.
2130To only install the version-specific parts of the perl installation, run
2131
2132 Configure -Dversiononly
2133
2134or answer 'y' to the appropriate Configure prompt. Alternatively,
2135you can just manually run
2136
2137 ./perl installperl -v
2138
2139and skip installman altogether.
33cceb07 2140
d56c5707
JH
2141See also L<"Maintaining completely separate versions"> for another
2142approach.
2143
f4ce0e6d
RGS
2144=head1 cd /usr/include; h2ph *.h sys/*.h
2145
2146Some perl scripts need to be able to obtain information from the
2147system header files. This command will convert the most commonly used
2148header files in /usr/include into files that can be easily interpreted
2149by perl. These files will be placed in the architecture-dependent
2150library ($archlib) directory you specified to Configure.
2151
2152Note: Due to differences in the C and perl languages, the conversion
2153of the header files is not perfect. You will probably have to
2154hand-edit some of the converted files to get them to parse correctly.
2155For example, h2ph breaks spectacularly on type casting and certain
2156structures.
2157
2158=head1 installhtml --help
2159
2160Some sites may wish to make perl documentation available in HTML
2161format. The installhtml utility can be used to convert pod
2162documentation into linked HTML files and install them.
2163
2164Currently, the supplied ./installhtml script does not make use of the
2165html Configure variables. This should be fixed in a future release.
2166
2167The following command-line is an example of one used to convert
2168perl documentation:
2169
2170 ./installhtml \
2171 --podroot=. \
2172 --podpath=lib:ext:pod:vms \
2173 --recurse \
2174 --htmldir=/perl/nmanual \
2175 --htmlroot=/perl/nmanual \
2176 --splithead=pod/perlipc \
2177 --splititem=pod/perlfunc \
2178 --libpods=perlfunc:perlguts:perlvar:perlrun:perlop \
2179 --verbose
2180
2181See the documentation in installhtml for more details. It can take
2182many minutes to execute a large installation and you should expect to
2183see warnings like "no title", "unexpected directive" and "cannot
2184resolve" as the files are processed. We are aware of these problems
2185(and would welcome patches for them).
2186
2187You may find it helpful to run installhtml twice. That should reduce
2188the number of "cannot resolve" warnings.
2189
2190=head1 cd pod && make tex && (process the latex files)
2191
2192Some sites may also wish to make the documentation in the pod/ directory
2193available in TeX format. Type
2194
2195 (cd pod && make tex && <process the latex files>)
2196
2197=head1 Starting all over again
2198
2199If you wish to re-build perl from the same build directory, you should
2200clean it out with the command
2201
2202 make distclean
2203
2204or
2205
2206 make realclean
2207
2208The only difference between the two is that make distclean also removes
2209your old config.sh and Policy.sh files.
2210
2211If you are upgrading from a previous version of perl, or if you
2212change systems or compilers or make other significant changes, or if
2213you are experiencing difficulties building perl, you should not re-use
2214your old config.sh.
2215
2216If your reason to reuse your old config.sh is to save your particular
2217installation choices, then you can probably achieve the same effect by
2218using the Policy.sh file. See the section on L<"Site-wide Policy
2219settings"> above.
2220
ff52061e
RGS
2221=head1 Reporting Problems
2222
2223Wherever possible please use the perlbug tool supplied with this Perl
2224to report problems, as it automatically includes summary configuration
2225information about your perl, which may help us track down problems far
2226more quickly. But first you should read the advice in this file,
2227carefully re-read the error message and check the relevant manual pages
2228on your system, as these may help you find an immediate solution. If
2229you are not sure whether what you are seeing is a bug, you can send a
2230message describing the problem to the comp.lang.perl.misc newsgroup to
2231get advice.
2232
2233The perlbug tool is installed along with perl, so after you have
2234completed C<make install> it should be possible to run it with plain
2235C<perlbug>. If the install fails, or you want to report problems with
2236C<make test> without installing perl, then you can use C<make nok> to
2237run perlbug to report the problem, or run it by hand from this source
2238directory with C<./perl -Ilib utils/perlbug>
2239
2240If the build fails too early to run perlbug uninstalled, then please
2241B<run> the C<./myconfig> shell script, and mail its output along with
2242an accurate description of your problem to perlbug@perl.org
2243
2244If Configure itself fails, and does not generate a config.sh file
2245(needed to run C<./myconfig>), then please mail perlbug@perl.org the
2246description of how Configure fails along with details of your system
2247- for example the output from running C<uname -a>
2248
2249Please try to make your message brief but clear. Brief, clear bug
2250reports tend to get answered more quickly. Please don't worry if your
2251written English is not great - what matters is how well you describe
2252the important technical details of the problem you have encountered,
2253not whether your grammar and spelling is flawless.
2254
2255Trim out unnecessary information. Do not include large files (such as
2256config.sh or a complete Configure or make log) unless absolutely
2257necessary. Do not include a complete transcript of your build
2258session. Just include the failing commands, the relevant error
2259messages, and whatever preceding commands are necessary to give the
2260appropriate context. Plain text should usually be sufficient--fancy
2261attachments or encodings may actually reduce the number of people who
2262read your message. Your message will get relayed to over 400
2263subscribers around the world so please try to keep it brief but clear.
2264
5acb7768
NC
2265If the bug you are reporting has security implications, which make it
2266inappropriate to send to a publicly archived mailing list, then please send
2267it to perl5-security-report@perl.org. This points to a closed subscription
2268unarchived mailing list, which includes all the core committers, who be able
2269to help assess the impact of issues, figure out a resolution, and help
2270co-ordinate the release of patches to mitigate or fix the problem across all
2271platforms on which Perl is supported. Please only use this address for security
2272issues in the Perl core, not for modules independently distributed on CPAN.
2273
ff52061e
RGS
2274If you are unsure what makes a good bug report please read "How to
2275report Bugs Effectively" by Simon Tatham:
2276http://www.chiark.greenend.org.uk/~sgtatham/bugs.html
2277
7df75831 2278=head1 Coexistence with earlier versions of perl 5
4633a7c4 2279
54c46bd5 2280Perl 5.11 is not binary compatible with earlier versions of Perl.
cc65bb49 2281In other words, you will have to recompile your XS modules.
14eee2f1 2282
693762b4 2283In general, you can usually safely upgrade from one version of Perl (e.g.
33cceb07
RGS
22845.X.Y) to another similar minor version (e.g. 5.X.(Y+1))) without
2285re-compiling all of your extensions. You can also safely leave the old
2286version around in case the new version causes you problems for some reason.
693762b4 2287
be8498a1
RGS
2288Usually, most extensions will probably not need to be recompiled to be
2289used with a newer version of Perl. Here is how it is supposed to work.
ce80d64e 2290(These examples assume you accept all the Configure defaults.)
693762b4 2291
33cceb07
RGS
2292Suppose you already have version 5.8.7 installed. The directories
2293searched by 5.8.7 are typically like:
d6baa268 2294
33cceb07
RGS
2295 /usr/local/lib/perl5/5.8.7/$archname
2296 /usr/local/lib/perl5/5.8.7
2297 /usr/local/lib/perl5/site_perl/5.8.7/$archname
2298 /usr/local/lib/perl5/site_perl/5.8.7
d6baa268 2299
33cceb07
RGS
2300Now, suppose you install version 5.8.8. The directories
2301searched by version 5.8.8 will be:
d6baa268 2302
33cceb07
RGS
2303 /usr/local/lib/perl5/5.8.8/$archname
2304 /usr/local/lib/perl5/5.8.8
2305 /usr/local/lib/perl5/site_perl/5.8.8/$archname
2306 /usr/local/lib/perl5/site_perl/5.8.8
d6baa268 2307
33cceb07
RGS
2308 /usr/local/lib/perl5/site_perl/5.8.7/$archname
2309 /usr/local/lib/perl5/site_perl/5.8.7
c42e3e15 2310 /usr/local/lib/perl5/site_perl/
bfb7748a 2311
c42e3e15 2312Notice the last three entries -- Perl understands the default structure
d6baa268 2313of the $sitelib directories and will look back in older, compatible
33cceb07
RGS
2314directories. This way, modules installed under 5.8.7 will continue
2315to be usable by 5.8.7 but will also accessible to 5.8.8. Further,
d6baa268 2316suppose that you upgrade a module to one which requires features
33cceb07
RGS
2317present only in 5.8.8. That new module will get installed into
2318/usr/local/lib/perl5/site_perl/5.8.8 and will be available to 5.8.8,
2319but will not interfere with the 5.8.7 version.
bfb7748a 2320
c42e3e15 2321The last entry, /usr/local/lib/perl5/site_perl/, is there so that
fe23a901 23225.6.0 and above will look for 5.004-era pure perl modules.
d6baa268 2323
33cceb07
RGS
2324Lastly, suppose you now install 5.10.0, which is not binary compatible
2325with 5.8.x. The directories searched by 5.10.0 (if you don't change the
fe23a901
RF
2326Configure defaults) will be:
2327
33cceb07
RGS
2328 /usr/local/lib/perl5/5.10.0/$archname
2329 /usr/local/lib/perl5/5.10.0
2330 /usr/local/lib/perl5/site_perl/5.10.0/$archname
2331 /usr/local/lib/perl5/site_perl/5.10.0
d6baa268 2332
33cceb07 2333 /usr/local/lib/perl5/site_perl/5.8.8
d6baa268 2334
33cceb07 2335 /usr/local/lib/perl5/site_perl/5.8.7
fe23a901 2336
d6baa268 2337 /usr/local/lib/perl5/site_perl/
bfb7748a 2338
cc65bb49
AD
2339Note that the earlier $archname entries are now gone, but pure perl
2340modules from earlier versions will still be found.
2341
0a08c020
GS
2342This way, you can choose to share compatible extensions, but also upgrade
2343to a newer version of an extension that may be incompatible with earlier
2344versions, without breaking the earlier versions' installations.
693762b4
AD
2345
2346=head2 Maintaining completely separate versions
4633a7c4 2347
1ec51d55 2348Many users prefer to keep all versions of perl in completely
d6baa268 2349separate directories. This guarantees that an update to one version
0a08c020
GS
2350won't interfere with another version. (The defaults guarantee this for
2351libraries after 5.6.0, but not for executables. TODO?) One convenient
2352way to do this is by using a separate prefix for each version, such as
d52d4e46 2353
54c46bd5 2354 sh Configure -Dprefix=/opt/perl5.11.0
d52d4e46 2355
54c46bd5 2356and adding /opt/perl5.11.0/bin to the shell PATH variable. Such users
d52d4e46
PP
2357may also wish to add a symbolic link /usr/local/bin/perl so that
2358scripts can still start with #!/usr/local/bin/perl.
2359
693762b4 2360Others might share a common directory for maintenance sub-versions
33cceb07 2361(e.g. 5.10 for all 5.10.x versions), but change directory with
693762b4
AD
2362each major version.
2363
6877a1cf
AD
2364If you are installing a development subversion, you probably ought to
2365seriously consider using a separate directory, since development
2366subversions may not have all the compatibility wrinkles ironed out
2367yet.
2368
54c46bd5 2369=head2 Upgrading from 5.10.x or earlier
693762b4 2370
54c46bd5 2371B<Perl 5.11.0 is binary incompatible with Perl 5.10.x and any earlier
dd3196cd 2372Perl release.> Perl modules having binary parts
e655887d 2373(meaning that a C compiler is used) will have to be recompiled to be
54c46bd5
JV
2374used with 5.11.0. If you find you do need to rebuild an extension with
23755.11.0, you may safely do so without disturbing the older
7df75831 2376installations. (See L<"Coexistence with earlier versions of perl 5">
e655887d 2377above.)
c42e3e15
GS
2378
2379See your installed copy of the perllocal.pod file for a (possibly
2380incomplete) list of locally installed modules. Note that you want
cc65bb49 2381perllocal.pod, not perllocale.pod, for installed module information.
693762b4 2382
8ebf57cf
JH
2383=head1 Minimizing the Perl installation
2384
2385The following section is meant for people worrying about squeezing the
2386Perl installation into minimal systems (for example when installing
2387operating systems, or in really small filesystems).
2388
c8214fdf 2389Leaving out as many extensions as possible is an obvious way:
5cda700b
AD
2390Encode, with its big conversion tables, consumes a lot of
2391space. On the other hand, you cannot throw away everything. The
2392Fcntl module is pretty essential. If you need to do network
c8214fdf
JH
2393programming, you'll appreciate the Socket module, and so forth: it all
2394depends on what do you need to do.
2395
8ebf57cf
JH
2396In the following we offer two different slimmed down installation
2397recipes. They are informative, not normative: the choice of files
2398depends on what you need.
2399
2400Firstly, the bare minimum to run this script
2401
2402 use strict;
2403 use warnings;
2404 foreach my $f (</*>) {
2405 print("$f\n");
2406 }
2407
bfe08c74 2408in Linux is as follows (under $Config{prefix}):
8ebf57cf
JH
2409
2410 ./bin/perl
bfe08c74
RGS
2411 ./lib/perl5/5.9.3/strict.pm
2412 ./lib/perl5/5.9.3/warnings.pm
2413 ./lib/perl5/5.9.3/i686-linux/File/Glob.pm
2414 ./lib/perl5/5.9.3/i686-linux/XSLoader.pm
2415 ./lib/perl5/5.9.3/i686-linux/auto/File/Glob/Glob.so
8ebf57cf
JH
2416
2417Secondly, Debian perl-base package contains the following files,
bfe08c74 2418size about 1.9MB in its i386 version:
8ebf57cf 2419
bfe08c74
RGS
2420 /usr/bin/perl
2421 /usr/bin/perl5.8.4
2422 /usr/lib/perl/5.8
2423 /usr/lib/perl/5.8.4/B.pm
2424 /usr/lib/perl/5.8.4/B/Deparse.pm
2425 /usr/lib/perl/5.8.4/Config.pm
2426 /usr/lib/perl/5.8.4/Cwd.pm
2427 /usr/lib/perl/5.8.4/Data/Dumper.pm
2428 /usr/lib/perl/5.8.4/DynaLoader.pm
2429 /usr/lib/perl/5.8.4/Errno.pm
2430 /usr/lib/perl/5.8.4/Fcntl.pm
2431 /usr/lib/perl/5.8.4/File/Glob.pm
2432 /usr/lib/perl/5.8.4/IO.pm
2433 /usr/lib/perl/5.8.4/IO/File.pm
2434 /usr/lib/perl/5.8.4/IO/Handle.pm
2435 /usr/lib/perl/5.8.4/IO/Pipe.pm
2436 /usr/lib/perl/5.8.4/IO/Seekable.pm
2437 /usr/lib/perl/5.8.4/IO/Select.pm
2438 /usr/lib/perl/5.8.4/IO/Socket.pm
2439 /usr/lib/perl/5.8.4/POSIX.pm
2440 /usr/lib/perl/5.8.4/Socket.pm
2441 /usr/lib/perl/5.8.4/XSLoader.pm
2442 /usr/lib/perl/5.8.4/auto/Cwd/Cwd.bs
2443 /usr/lib/perl/5.8.4/auto/Cwd/Cwd.so
2444 /usr/lib/perl/5.8.4/auto/Data/Dumper/Dumper.bs
2445 /usr/lib/perl/5.8.4/auto/Data/Dumper/Dumper.so
2446 /usr/lib/perl/5.8.4/auto/DynaLoader/DynaLoader.a
2447 /usr/lib/perl/5.8.4/auto/DynaLoader/autosplit.ix
2448 /usr/lib/perl/5.8.4/auto/DynaLoader/dl_expandspec.al
2449 /usr/lib/perl/5.8.4/auto/DynaLoader/dl_find_symbol_anywhere.al
2450 /usr/lib/perl/5.8.4/auto/DynaLoader/dl_findfile.al
2451 /usr/lib/perl/5.8.4/auto/DynaLoader/extralibs.ld
2452 /usr/lib/perl/5.8.4/auto/Fcntl/Fcntl.bs
2453 /usr/lib/perl/5.8.4/auto/Fcntl/Fcntl.so
2454 /usr/lib/perl/5.8.4/auto/File/Glob/Glob.bs
2455 /usr/lib/perl/5.8.4/auto/File/Glob/Glob.so
2456 /usr/lib/perl/5.8.4/auto/IO/IO.bs
2457 /usr/lib/perl/5.8.4/auto/IO/IO.so
2458 /usr/lib/perl/5.8.4/auto/POSIX/POSIX.bs
2459 /usr/lib/perl/5.8.4/auto/POSIX/POSIX.so
2460 /usr/lib/perl/5.8.4/auto/POSIX/autosplit.ix
2461 /usr/lib/perl/5.8.4/auto/POSIX/load_imports.al
2462 /usr/lib/perl/5.8.4/auto/Socket/Socket.bs
2463 /usr/lib/perl/5.8.4/auto/Socket/Socket.so
2464 /usr/lib/perl/5.8.4/lib.pm
2465 /usr/lib/perl/5.8.4/re.pm
2466 /usr/share/doc/perl-base
8ebf57cf 2467 /usr/share/doc/perl/AUTHORS.gz
bfe08c74
RGS
2468 /usr/share/doc/perl/Documentation
2469 /usr/share/doc/perl/README.Debian.gz
8ebf57cf 2470 /usr/share/doc/perl/changelog.Debian.gz
bfe08c74 2471 /usr/share/doc/perl/copyright
8ebf57cf 2472 /usr/share/man/man1/perl.1.gz
bfe08c74
RGS
2473 /usr/share/perl/5.8
2474 /usr/share/perl/5.8.4/AutoLoader.pm
2475 /usr/share/perl/5.8.4/Carp.pm
2476 /usr/share/perl/5.8.4/Carp/Heavy.pm
2477 /usr/share/perl/5.8.4/Exporter.pm
2478 /usr/share/perl/5.8.4/Exporter/Heavy.pm
2479 /usr/share/perl/5.8.4/File/Spec.pm
2480 /usr/share/perl/5.8.4/File/Spec/Unix.pm
2481 /usr/share/perl/5.8.4/FileHandle.pm
2482 /usr/share/perl/5.8.4/Getopt/Long.pm
2483 /usr/share/perl/5.8.4/IO/Socket/INET.pm
2484 /usr/share/perl/5.8.4/IO/Socket/UNIX.pm
2485 /usr/share/perl/5.8.4/IPC/Open2.pm
2486 /usr/share/perl/5.8.4/IPC/Open3.pm
2487 /usr/share/perl/5.8.4/List/Util.pm
2488 /usr/share/perl/5.8.4/Scalar/Util.pm
2489 /usr/share/perl/5.8.4/SelectSaver.pm
2490 /usr/share/perl/5.8.4/Symbol.pm
2491 /usr/share/perl/5.8.4/Text/ParseWords.pm
2492 /usr/share/perl/5.8.4/Text/Tabs.pm
2493 /usr/share/perl/5.8.4/Text/Wrap.pm
2494 /usr/share/perl/5.8.4/attributes.pm
2495 /usr/share/perl/5.8.4/base.pm
2496 /usr/share/perl/5.8.4/bytes.pm
2497 /usr/share/perl/5.8.4/bytes_heavy.pl
2498 /usr/share/perl/5.8.4/constant.pm
2499 /usr/share/perl/5.8.4/fields.pm
2500 /usr/share/perl/5.8.4/integer.pm
2501 /usr/share/perl/5.8.4/locale.pm
2502 /usr/share/perl/5.8.4/overload.pm
2503 /usr/share/perl/5.8.4/strict.pm
2504 /usr/share/perl/5.8.4/utf8.pm
2505 /usr/share/perl/5.8.4/utf8_heavy.pl
2506 /usr/share/perl/5.8.4/vars.pm
2507 /usr/share/perl/5.8.4/warnings.pm
2508 /usr/share/perl/5.8.4/warnings/register.pm
8ebf57cf 2509
e7a3c61b
JH
2510A nice trick to find out the minimal set of Perl library files you will
2511need to run a Perl program is
2512
a0a8d9d3 2513 perl -e 'do "prog.pl"; END { print "$_\n" for sort keys %INC }'
e7a3c61b
JH
2514
2515(this will not find libraries required in runtime, unfortunately, but
2516it's a minimal set) and if you want to find out all the files you can
2517use something like the below
2518
2519 strace perl -le 'do "x.pl"' 2>&1 | perl -nle '/^open\(\"(.+?)"/ && print $1'
2520
2521(The 'strace' is Linux-specific, other similar utilities include 'truss'
2522and 'ktrace'.)
2523
c19ccd8c
RGS
2524=head2 C<-DNO_MATHOMS>
2525
2526If you configure perl with C<-Accflags=-DNO_MATHOMS>, the functions from
2527F<mathoms.c> will not be compiled in. Those functions are no longer used
2528by perl itself; for source compatibility reasons, though, they weren't
2529completely removed.
2530
8e07c86e
AD
2531=head1 DOCUMENTATION
2532
bfb7748a
AD
2533Read the manual entries before running perl. The main documentation
2534is in the pod/ subdirectory and should have been installed during the
8e07c86e 2535build process. Type B<man perl> to get started. Alternatively, you
bfb7748a
AD
2536can type B<perldoc perl> to use the supplied perldoc script. This is
2537sometimes useful for finding things in the library modules.
8e07c86e
AD
2538
2539=head1 AUTHOR
2540
bfb7748a
AD
2541Original author: Andy Dougherty doughera@lafayette.edu , borrowing very
2542heavily from the original README by Larry Wall, with lots of helpful
2543feedback and additions from the perl5-porters@perl.org folks.
fb73857a 2544
f5b3b617
AD
2545If you have problems, corrections, or questions, please see
2546L<"Reporting Problems"> above.
2547
2548=head1 REDISTRIBUTION
2549
2550This document is part of the Perl package and may be distributed under
d6baa268 2551the same terms as perl itself, with the following additional request:
f5b3b617 2552If you are distributing a modified version of perl (perhaps as part of
d6baa268
JH
2553a larger package) please B<do> modify these installation instructions
2554and the contact information to match your distribution.