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[perl #9328] Update INSTALL example for BerkeleyDB install
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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
c3edaffb 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
fb73857a 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
247(5005threads) has been 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
c3edaffb 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
c3edaffb 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
c3edaffb 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
c3edaffb 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.
c3edaffb 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
c3edaffb 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
c3edaffb 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
08854360 527By default, Configure will use the following directories for 5.10.0.
ce80d64e 528$version is the full perl version number, including subversion, e.g.
08854360 5295.10.0 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
ce80d64e 775=head2 Site-wide Policy settings
55479bb6 776
ce80d64e 777After Configure runs, it stores a number of common site-wide "policy"
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778answers (such as installation directories) in the Policy.sh file.
779If you want to build perl on another system using the same policy
780defaults, simply copy the Policy.sh file to the new system's perl build
781directory, and Configure will use it. This will work even if Policy.sh was
a0a8d9d3 782generated for another version of Perl, or on a system with a
da1b4322 783different architecture and/or operating system. However, in such cases,
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784you should review the contents of the file before using it: for
785example, your new target may not keep its man pages in the same place
786as the system on which the file was generated.
55479bb6 787
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788Alternatively, if you wish to change some or all of those policy
789answers, you should
c3edaffb 790
ce80d64e 791 rm -f Policy.sh
aa689395 792
ce80d64e 793to ensure that Configure doesn't re-use them.
2ae324a7 794
ce80d64e 795Further information is in the Policy_sh.SH file itself.
aa689395 796
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797If the generated Policy.sh file is unsuitable, you may freely edit it
798to contain any valid shell commands. It will be run just after the
799platform-specific hints files.
aa689395 800
ce80d64e 801=head2 Disabling older versions of Perl
aa689395 802
ce80d64e 803Configure will search for binary compatible versions of previously
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804installed perl binaries in the tree that is specified as target tree,
805and these will be used as locations to search for modules by the perl
806being built. The list of perl versions found will be put in the Configure
807variable inc_version_list.
86058a2d 808
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809To disable this use of older perl modules, even completely valid pure perl
810modules, you can specify to not include the paths found:
b2a6d19e 811
ce80d64e 812 sh Configure -Dinc_version_list=none ...
d6baa268 813
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814When using the newer perl, you can add these paths again in the
815$PERL5LIB environment variable or with perl's -I runtime option.
86058a2d 816
ce80d64e 817=head2 Building Perl outside of the source directory
86058a2d 818
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819Sometimes it is desirable to build Perl in a directory different from
820where the sources are, for example if you want to keep your sources
821read-only, or if you want to share the sources between different binary
822architectures. You can do this (if your file system supports symbolic
823links) by
06c896bb 824
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825 mkdir /tmp/perl/build/directory
826 cd /tmp/perl/build/directory
827 sh /path/to/perl/source/Configure -Dmksymlinks ...
06c896bb 828
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829This will create in /tmp/perl/build/directory a tree of symbolic links
830pointing to files in /path/to/perl/source. The original files are left
831unaffected. After Configure has finished you can just say
06c896bb 832
ce80d64e 833 make
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834 make test
835 make install
06c896bb 836
ce80d64e 837as usual, and Perl will be built in /tmp/perl/build/directory.
aa689395 838
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839=head2 Building a debugging perl
840
841You can run perl scripts under the perl debugger at any time with
3fe9a6f1 842B<perl -d your_script>. If, however, you want to debug perl itself,
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843you probably want to have support for perl internal debugging code
844(activated by adding -DDEBUGGING to ccflags), and/or support for the
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845system debugger by adding -g to the optimisation flags. For that,
846use the parameter:
eaf812ae 847
08854360
RGS
848 sh Configure -DDEBUGGING
849
850or
851
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852 sh Configure -DDEBUGGING=<mode>
853
854For a more eye appealing call, -DEBUGGING is defined to be an alias
855for -DDEBUGGING. For both, the -U calls are also supported, in order
856to be able to overrule the hints or Policy.sh settings.
857
7df75831 858Here are the DEBUGGING modes:
3bf462b8 859
7df75831 860=over 4
3bf462b8 861
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862=item -DDEBUGGING
863
864=item -DEBUGGING
865
866=item -DEBUGGING=both
867
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868Sets both -DDEBUGGING in the ccflags, and adds -g to optimize.
869
870You can actually specify -g and -DDEBUGGING independently (see below),
871but usually it's convenient to have both.
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872
873=item -DEBUGGING=-g
874
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875=item -Doptimize=-g
876
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877Adds -g to optimize, but does not set -DDEBUGGING.
878
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879(Note: Your system may actually require something like cc -g2.
880Check your man pages for cc(1) and also any hint file for your system.)
881
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882=item -DEBUGGING=none
883
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884=item -UDEBUGGING
885
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886Removes -g from optimize, and -DDEBUGGING from ccflags.
887
888=back
889
3bf462b8 890If you are using a shared libperl, see the warnings about multiple
a522f097 891versions of perl under L<Building a shared Perl library>.
3bf462b8 892
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893=head2 Extensions
894
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895Perl ships with a number of standard extensions. These are contained
896in the ext/ subdirectory.
897
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898By default, Configure will offer to build every extension which appears
899to be supported. For example, Configure will offer to build GDBM_File
7df75831 900only if it is able to find the gdbm library.
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901
902To disable certain extensions so that they are not built, use the
903-Dnoextensions=... and -Donlyextensions=... options. They both accept
904a space-separated list of extensions. The extensions listed in
905C<noextensions> are removed from the list of extensions to build, while
906the C<onlyextensions> is rather more severe and builds only the listed
907extensions. The latter should be used with extreme caution since
908certain extensions are used by many other extensions and modules:
909examples of such modules include Fcntl and IO. The order of processing
910these options is first C<only> (if present), then C<no> (if present).
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911
912Of course, you may always run Configure interactively and select only
913the extensions you want.
914
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915If you unpack any additional extensions in the ext/ directory before
916running Configure, then Configure will offer to build those additional
917extensions as well. Most users probably shouldn't have to do this --
918it is usually easier to build additional extensions later after perl
919has been installed. However, if you wish to have those additional
920extensions statically linked into the perl binary, then this offers a
921convenient way to do that in one step. (It is not necessary, however;
922you can build and install extensions just fine even if you don't have
923dynamic loading. See lib/ExtUtils/MakeMaker.pm for more details.)
924Another way of specifying extra modules is described in
925L<"Adding extra modules to the build"> below.
8d74ce1c 926
dd3196cd 927If you re-use an old config.sh but change your system (e.g. by
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928adding libgdbm) Configure will still offer your old choices of extensions
929for the default answer, but it will also point out the discrepancy to
930you.
931
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932=head2 Including locally-installed libraries
933
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934Perl comes with interfaces to number of libraries, including threads,
935dbm, ndbm, gdbm, and Berkeley db. For the *db* extension, if
8d74ce1c 936Configure can find the appropriate header files and libraries, it will
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937automatically include that extension. The threading extension needs
938to be specified explicitely (see L<Threads>).
939
940Those libraries are not distributed with perl. If your header (.h) files
941for those libraries are not in a directory normally searched by your C
942compiler, then you will need to include the appropriate -I/your/directory
943option when prompted by Configure. If your libraries are not in a
944directory normally searched by your C compiler and linker, then you will
945need to include the appropriate -L/your/directory option when prompted
946by Configure. See the examples below.
8d74ce1c 947
ce80d64e 948=head3 Examples
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949
950=over 4
951
952=item gdbm in /usr/local
953
954Suppose you have gdbm and want Configure to find it and build the
d6baa268 955GDBM_File extension. This example assumes you have gdbm.h
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956installed in /usr/local/include/gdbm.h and libgdbm.a installed in
957/usr/local/lib/libgdbm.a. Configure should figure all the
958necessary steps out automatically.
959
960Specifically, when Configure prompts you for flags for
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961your C compiler, you should include -I/usr/local/include, if it's
962not here yet. Similarly, when Configure prompts you for linker flags,
963you should include -L/usr/local/lib.
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964
965If you are using dynamic loading, then when Configure prompts you for
966linker flags for dynamic loading, you should again include
967-L/usr/local/lib.
968
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969Again, this should all happen automatically. This should also work if
970you have gdbm installed in any of (/usr/local, /opt/local, /usr/gnu,
971/opt/gnu, /usr/GNU, or /opt/GNU).
8d74ce1c 972
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973=item BerkeleyDB in /usr/local/BerkeleyDB
974
975The version of BerkeleyDB distributed by sleepycat.com installs in a
976version-specific directory by default, typically something like
977/usr/local/BerkeleyDB.4.7. To have Configure find that, you need to add
978-I/usr/local/BerkeleyDB.4.7/include to cc flags, as in the previous example,
979and you will also have to take extra steps to help Configure find -ldb.
980Specifically, when Configure prompts you for library directories,
981add /usr/local/BerkeleyDB.4.7/lib to the list. Also, you will need to
982add appropriate linker flags to tell the runtime linker where to find the
983BerkeleyDB shared libraries.
984
985It is possible to specify this from the command line (all on one
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986line):
987
7df75831 988 sh Configure -de \
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989 -Dlocincpth='/usr/local/BerkeleyDB.4.7/include /usr/local/include' \
990 -Dloclibpth='/usr/local/BerkeleyDB.4.7/lib /usr/local/lib' \
991 -Aldflags='-R/usr/local/BerkeleyDB.4.7/lib'
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992
993locincpth is a space-separated list of include directories to search.
994Configure will automatically add the appropriate -I directives.
995
996loclibpth is a space-separated list of library directories to search.
e8b9ce60 997Configure will automatically add the appropriate -L directives.
8d74ce1c 998
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999The addition to ldflags is so that the dynamic linker knows where to find
1000the BerkeleyDB libraries. For Linux and Solaris, the -R option does that.
1001Other systems may use different flags. Use the appropriate flag for your
1002system.
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1003
1004=back
1005
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1006=head2 Overriding an old config.sh
1007
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1008If you want to use an old config.sh produced by a previous run of
1009Configure, but override some of the items with command line options, you
1010need to use B<Configure -O>.
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1011
1012=head2 GNU-style configure
1013
1014If you prefer the GNU-style configure command line interface, you can
1015use the supplied configure.gnu command, e.g.
1016
1017 CC=gcc ./configure.gnu
1018
1019The configure.gnu script emulates a few of the more common configure
1020options. Try
1021
1022 ./configure.gnu --help
1023
1024for a listing.
1025
1026(The file is called configure.gnu to avoid problems on systems
1027that would not distinguish the files "Configure" and "configure".)
1028
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1029=head2 Malloc Issues
1030
1031Perl relies heavily on malloc(3) to grow data structures as needed,
1032so perl's performance can be noticeably affected by the performance of
1033the malloc function on your system. The perl source is shipped with a
1034version of malloc that has been optimized for the typical requests from
1035perl, so there's a chance that it may be both faster and use less memory
1036than your system malloc.
1037
1038However, if your system already has an excellent malloc, or if you are
1039experiencing difficulties with extensions that use third-party libraries
1040that call malloc, then you should probably use your system's malloc.
1041(Or, you might wish to explore the malloc flags discussed below.)
1042
1043=over 4
1044
1045=item Using the system malloc
1046
1047To build without perl's malloc, you can use the Configure command
1048
1049 sh Configure -Uusemymalloc
1050
1051or you can answer 'n' at the appropriate interactive Configure prompt.
1052
73d6d1b0
RGS
1053Note that Perl's malloc isn't always used by default; that actually
1054depends on your system. For example, on Linux and FreeBSD (and many more
1055systems), Configure chooses to use the system's malloc by default.
1056See the appropriate file in the F<hints/> directory to see how the
1057default is set.
1058
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1059=item -DPERL_POLLUTE_MALLOC
1060
1061NOTE: This flag is enabled automatically on some platforms if you just
7df75831 1062run Configure to accept all the defaults.
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1063
1064Perl's malloc family of functions are normally called Perl_malloc(),
1065Perl_realloc(), Perl_calloc() and Perl_mfree().
1066These names do not clash with the system versions of these functions.
1067
1068If this flag is enabled, however, Perl's malloc family of functions
1069will have the same names as the system versions. This may be required
1070sometimes if you have libraries that like to free() data that may have
1071been allocated by Perl_malloc() and vice versa.
1072
1073Note that enabling this option may sometimes lead to duplicate symbols
1074from the linker for malloc et al. In such cases, the system probably
1075does not allow its malloc functions to be fully replaced with custom
1076versions.
1077
1078=item -DPERL_DEBUGGING_MSTATS
1079
1080This flag enables debugging mstats, which is required to use the
1081Devel::Peek::mstat() function. You cannot enable this unless you are
1082using Perl's malloc, so a typical Configure command would be
1083
7df75831 1084 sh Configure -Accflags=-DPERL_DEBUGGING_MSTATS -Dusemymalloc
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1085
1086to enable this option.
1087
1088=back
1089
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1090=head2 What if it doesn't work?
1091
8d74ce1c 1092If you run into problems, try some of the following ideas.
ff52061e 1093If none of them help, then see L<"Reporting Problems"> below.
8d74ce1c 1094
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1095=over 4
1096
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1097=item Running Configure Interactively
1098
1099If Configure runs into trouble, remember that you can always run
1100Configure interactively so that you can check (and correct) its
1101guesses.
1102
1103All the installation questions have been moved to the top, so you don't
aa689395 1104have to wait for them. Once you've handled them (and your C compiler and
1ec51d55 1105flags) you can type &-d at the next Configure prompt and Configure
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1106will use the defaults from then on.
1107
1108If you find yourself trying obscure command line incantations and
1109config.over tricks, I recommend you run Configure interactively
1110instead. You'll probably save yourself time in the long run.
1111
aa689395 1112=item Hint files
8e07c86e 1113
a0a8d9d3
DD
1114Hint files tell Configure about a number of things:
1115
1116=over 4
1117
1118=item o
1119
1120The peculiarities or conventions of particular platforms -- non-standard
1121library locations and names, default installation locations for binaries,
1122and so on.
1123
1124=item o
1125
1126The deficiencies of the platform -- for example, library functions that,
1127although present, are too badly broken to be usable; or limits on
1128resources that are generously available on most platforms.
1129
1130=item o
1131
1132How best to optimize for the platform, both in terms of binary size and/or
1133speed, and for Perl feature support. Because of wide variations in the
1134implementation of shared libraries and of threading, for example, Configure
1135often needs hints in order to be able to use these features.
1136
1137=back
1138
1139The perl distribution includes many system-specific hints files
1140in the hints/ directory. If one of them matches your system, Configure
1141will offer to use that hint file. Unless you have a very good reason
1142not to, you should accept its offer.
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1143
1144Several of the hint files contain additional important information.
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1145If you have any problems, it is a good idea to read the relevant hint file
1146for further information. See hints/solaris_2.sh for an extensive example.
1147More information about writing good hints is in the hints/README.hints
a0a8d9d3
DD
1148file, which also explains hint files known as callback-units.
1149
1150Note that any hint file is read before any Policy file, meaning that
1151Policy overrides hints -- see L</Site-wide Policy settings>.
8e07c86e 1152
73d6d1b0 1153=item WHOA THERE!!!
edb1cbcb 1154
82c11e95
RGS
1155If you are re-using an old config.sh, it's possible that Configure detects
1156different values from the ones specified in this file. You will almost
1157always want to keep the previous value, unless you have changed something
1158on your system.
edb1cbcb 1159
1160For example, suppose you have added libgdbm.a to your system
1161and you decide to reconfigure perl to use GDBM_File. When you run
1162Configure again, you will need to add -lgdbm to the list of libraries.
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1163Now, Configure will find your gdbm include file and library and will
1164issue a message:
edb1cbcb 1165
1166 *** WHOA THERE!!! ***
1167 The previous value for $i_gdbm on this machine was "undef"!
1168 Keep the previous value? [y]
1169
1ec51d55 1170In this case, you do not want to keep the previous value, so you
c3edaffb 1171should answer 'n'. (You'll also have to manually add GDBM_File to
edb1cbcb 1172the list of dynamic extensions to build.)
1173
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1174=item Changing Compilers
1175
1176If you change compilers or make other significant changes, you should
1ec51d55 1177probably not re-use your old config.sh. Simply remove it or
dd3196cd 1178rename it, then rerun Configure with the options you want to use.
8e07c86e 1179
c3edaffb 1180=item Propagating your changes to config.sh
8e07c86e 1181
1ec51d55
CS
1182If you make any changes to config.sh, you should propagate
1183them to all the .SH files by running
1184
1185 sh Configure -S
1186
1187You will then have to rebuild by running
9d67150a 1188
1189 make depend
1190 make
8e07c86e 1191
48370efc
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1192=item config.over and config.arch
1193
1194You can also supply a shell script config.over to over-ride
1195Configure's guesses. It will get loaded up at the very end, just
1196before config.sh is created. You have to be careful with this,
1197however, as Configure does no checking that your changes make sense.
1198This file is usually good for site-specific customizations.
1199
1200There is also another file that, if it exists, is loaded before the
1201config.over, called config.arch. This file is intended to be per
1202architecture, not per site, and usually it's the architecture-specific
1203hints file that creates the config.arch.
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1204
1205=item config.h
1206
1ec51d55
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1207Many of the system dependencies are contained in config.h.
1208Configure builds config.h by running the config_h.SH script.
1209The values for the variables are taken from config.sh.
8e07c86e 1210
1ec51d55
CS
1211If there are any problems, you can edit config.h directly. Beware,
1212though, that the next time you run Configure, your changes will be
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1213lost.
1214
1215=item cflags
1216
1217If you have any additional changes to make to the C compiler command
1ec51d55
CS
1218line, they can be made in cflags.SH. For instance, to turn off the
1219optimizer on toke.c, find the line in the switch structure for
1220toke.c and put the command optimize='-g' before the ;; . You
1221can also edit cflags directly, but beware that your changes will be
1222lost the next time you run Configure.
8e07c86e 1223
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1224To explore various ways of changing ccflags from within a hint file,
1225see the file hints/README.hints.
1226
1227To change the C flags for all the files, edit config.sh and change either
1228$ccflags or $optimize, and then re-run
1ec51d55
CS
1229
1230 sh Configure -S
1231 make depend
8e07c86e 1232
aa689395 1233=item No sh
8e07c86e 1234
c42e3e15
GS
1235If you don't have sh, you'll have to copy the sample file
1236Porting/config.sh to config.sh and edit your config.sh to reflect your
1237system's peculiarities. See Porting/pumpkin.pod for more information.
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1238You'll probably also have to extensively modify the extension building
1239mechanism.
1240
c3edaffb 1241=item Porting information
1242
e6f03d26 1243Specific information for the OS/2, Plan 9, VMS and Win32 ports is in the
1ec51d55
CS
1244corresponding README files and subdirectories. Additional information,
1245including a glossary of all those config.sh variables, is in the Porting
ce80d64e 1246subdirectory. Porting/Glossary should especially come in handy.
c3edaffb 1247
7f678428 1248Ports for other systems may also be available. You should check out
468f45d5 1249http://www.cpan.org/ports for current information on ports to
7f678428 1250various other operating systems.
1251
ce80d64e 1252If you plan to port Perl to a new architecture, study carefully the
491517e0
JA
1253section titled "Philosophical Issues in Patching and Porting Perl"
1254in the file Porting/pumpkin.pod and the file Porting/patching.pod.
1255Study also how other non-UNIX ports have solved problems.
1256
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1257=back
1258
ce80d64e 1259=head2 Adding extra modules to the build
fadf0ef5
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1260
1261You can specify extra modules or module bundles to be fetched from the
1262CPAN and installed as part of the Perl build. Either use the -Dextras=...
1263command line parameter to Configure, for example like this:
1264
d3df0cfd 1265 Configure -Dextras="Bundle::LWP DBI"
fadf0ef5
JH
1266
1267or answer first 'y' to the question 'Install any extra modules?' and
d3df0cfd 1268then answer "Bundle::LWP DBI" to the 'Extras?' question.
fadf0ef5 1269The module or the bundle names are as for the CPAN module 'install' command.
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1270This will only work if those modules are to be built as dynamic
1271extensions. If you wish to include those extra modules as static
1272extensions, see L<"Extensions"> above.
fadf0ef5
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1273
1274Notice that because the CPAN module will be used to fetch the extra
1275modules, you will need access to the CPAN, either via the Internet,
1276or via a local copy such as a CD-ROM or a local CPAN mirror. If you
1277do not, using the extra modules option will die horribly.
1278
1279Also notice that you yourself are responsible for satisfying any extra
1280dependencies such as external headers or libraries BEFORE trying the build.
d3df0cfd 1281For example: you will need to have the Foo database specific
fadf0ef5
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1282headers and libraries installed for the DBD::Foo module. The Configure
1283process or the Perl build process will not help you with these.
1284
ce80d64e 1285=head2 suidperl
03739d21 1286
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1287suidperl is an optional component, which is normally neither built
1288nor installed by default. From perlfaq1:
03739d21
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1289
1290 On some systems, setuid and setgid scripts (scripts written
1291 in the C shell, Bourne shell, or Perl, for example, with the
1292 set user or group ID permissions enabled) are insecure due to
1293 a race condition in the kernel. For those systems, Perl versions
1294 5 and 4 attempt to work around this vulnerability with an optional
1295 component, a special program named suidperl, also known as sperl.
1296 This program attempts to emulate the set-user-ID and set-group-ID
1297 features of the kernel.
1298
1299Because of the buggy history of suidperl, and the difficulty
1300of properly security auditing as large and complex piece of
1301software as Perl, we cannot recommend using suidperl and the feature
1302should be considered deprecated.
08854360 1303
ce80d64e 1304Instead, use a tool specifically designed to handle changes in
08854360 1305privileges, such as B<sudo>.
03739d21 1306
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1307=head1 make depend
1308
bfb7748a
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1309This will look for all the includes. The output is stored in makefile.
1310The only difference between Makefile and makefile is the dependencies at
1311the bottom of makefile. If you have to make any changes, you should edit
ce80d64e 1312makefile, not Makefile, since the Unix make command reads makefile first.
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1313(On non-Unix systems, the output may be stored in a different file.
1314Check the value of $firstmakefile in your config.sh if in doubt.)
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1315
1316Configure will offer to do this step for you, so it isn't listed
1317explicitly above.
1318
1319=head1 make
1320
1321This will attempt to make perl in the current directory.
1322
8d410bc4
YST
1323=head2 Expected errors
1324
f5b5f377 1325These error reports are normal, and can be ignored:
8d410bc4
YST
1326
1327 ...
1328 make: [extra.pods] Error 1 (ignored)
1329 ...
1330 make: [extras.make] Error 1 (ignored)
1331
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1332=head2 What if it doesn't work?
1333
8e07c86e 1334If you can't compile successfully, try some of the following ideas.
7f678428 1335If none of them help, and careful reading of the error message and
8d74ce1c 1336the relevant manual pages on your system doesn't help,
ff52061e 1337then see L<"Reporting Problems"> below.
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1338
1339=over 4
1340
1ec51d55 1341=item hints
8e07c86e
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1342
1343If you used a hint file, try reading the comments in the hint file
1344for further tips and information.
1345
1ec51d55 1346=item extensions
8e07c86e 1347
1ec51d55 1348If you can successfully build miniperl, but the process crashes
ce80d64e 1349during the building of extensions, run
c3edaffb 1350
3a6175e1 1351 make minitest
c3edaffb 1352
1353to test your version of miniperl.
1354
e57fd563 1355=item locale
1356
bfb7748a
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1357If you have any locale-related environment variables set, try unsetting
1358them. I have some reports that some versions of IRIX hang while
1359running B<./miniperl configpm> with locales other than the C locale.
1360See the discussion under L<"make test"> below about locales and the
08854360 1361whole L<perllocale/"LOCALE PROBLEMS"> section in the file pod/perllocale.pod.
3e6e419a
JH
1362The latter is especially useful if you see something like this
1363
1364 perl: warning: Setting locale failed.
1365 perl: warning: Please check that your locale settings:
1366 LC_ALL = "En_US",
1367 LANG = (unset)
1368 are supported and installed on your system.
1369 perl: warning: Falling back to the standard locale ("C").
1370
1371at Perl startup.
e57fd563 1372
7f678428 1373=item varargs
c3edaffb 1374
1375If you get varargs problems with gcc, be sure that gcc is installed
bfb7748a
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1376correctly and that you are not passing -I/usr/include to gcc. When using
1377gcc, you should probably have i_stdarg='define' and i_varargs='undef'
ce80d64e 1378in config.sh. The problem is usually solved by installing gcc
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1379correctly. If you do change config.sh, don't forget to propagate
1380your changes (see L<"Propagating your changes to config.sh"> below).
7f678428 1381See also the L<"vsprintf"> item below.
c3edaffb 1382
bfb7748a 1383=item util.c
c3edaffb 1384
1385If you get error messages such as the following (the exact line
bfb7748a 1386numbers and function name may vary in different versions of perl):
c3edaffb 1387
bfb7748a
AD
1388 util.c: In function `Perl_form':
1389 util.c:1107: number of arguments doesn't match prototype
1390 proto.h:125: prototype declaration
c3edaffb 1391
1392it might well be a symptom of the gcc "varargs problem". See the
7f678428 1393previous L<"varargs"> item.
c3edaffb 1394
1ec51d55 1395=item LD_LIBRARY_PATH
c3edaffb 1396
1397If you run into dynamic loading problems, check your setting of
aa689395 1398the LD_LIBRARY_PATH environment variable. If you're creating a static
1399Perl library (libperl.a rather than libperl.so) it should build
c3edaffb 1400fine with LD_LIBRARY_PATH unset, though that may depend on details
1401of your local set-up.
1402
aa689395 1403=item nm extraction
c3edaffb 1404
1405If Configure seems to be having trouble finding library functions,
1406try not using nm extraction. You can do this from the command line
1407with
1408
1409 sh Configure -Uusenm
1410
1411or by answering the nm extraction question interactively.
1ec51d55 1412If you have previously run Configure, you should not reuse your old
c3edaffb 1413config.sh.
1414
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1415=item umask not found
1416
1417If the build processes encounters errors relating to umask(), the problem
1418is probably that Configure couldn't find your umask() system call.
1419Check your config.sh. You should have d_umask='define'. If you don't,
1420this is probably the L<"nm extraction"> problem discussed above. Also,
1421try reading the hints file for your system for further information.
1422
7f678428 1423=item vsprintf
c3edaffb 1424
1425If you run into problems with vsprintf in compiling util.c, the
1426problem is probably that Configure failed to detect your system's
1427version of vsprintf(). Check whether your system has vprintf().
1428(Virtually all modern Unix systems do.) Then, check the variable
1429d_vprintf in config.sh. If your system has vprintf, it should be:
1430
1431 d_vprintf='define'
1432
1433If Configure guessed wrong, it is likely that Configure guessed wrong
bfb7748a
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1434on a number of other common functions too. This is probably
1435the L<"nm extraction"> problem discussed above.
c3edaffb 1436
3fe9a6f1 1437=item do_aspawn
1438
1439If you run into problems relating to do_aspawn or do_spawn, the
1440problem is probably that Configure failed to detect your system's
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1441fork() function. Follow the procedure in the previous item
1442on L<"nm extraction">.
3fe9a6f1 1443
84902520
TB
1444=item __inet_* errors
1445
1446If you receive unresolved symbol errors during Perl build and/or test
1447referring to __inet_* symbols, check to see whether BIND 8.1 is
1448installed. It installs a /usr/local/include/arpa/inet.h that refers to
1449these symbols. Versions of BIND later than 8.1 do not install inet.h
1450in that location and avoid the errors. You should probably update to a
6d240721
JH
1451newer version of BIND (and remove the files the old one left behind).
1452If you can't, you can either link with the updated resolver library provided
1453with BIND 8.1 or rename /usr/local/bin/arpa/inet.h during the Perl build and
1454test process to avoid the problem.
1455
73d6d1b0 1456=item .*_r() prototype NOT found
6d240721
JH
1457
1458On a related note, if you see a bunch of complaints like the above about
1459reentrant functions - specifically networking-related ones - being present
1460but without prototypes available, check to see if BIND 8.1 (or possibly
1461other BIND 8 versions) is (or has been) installed. They install
1462header files such as netdb.h into places such as /usr/local/include (or into
1463another directory as specified at build/install time), at least optionally.
f1300be0 1464Remove them or put them in someplace that isn't in the C preprocessor's
6d240721
JH
1465header file include search path (determined by -I options plus defaults,
1466normally /usr/include).
84902520 1467
d6baa268
JH
1468=item #error "No DATAMODEL_NATIVE specified"
1469
1470This is a common error when trying to build perl on Solaris 2.6 with a
1471gcc installation from Solaris 2.5 or 2.5.1. The Solaris header files
1472changed, so you need to update your gcc installation. You can either
1473rerun the fixincludes script from gcc or take the opportunity to
1474update your gcc installation.
1475
aa689395 1476=item Optimizer
c3edaffb 1477
9d67150a 1478If you can't compile successfully, try turning off your compiler's
aa689395 1479optimizer. Edit config.sh and change the line
9d67150a 1480
1481 optimize='-O'
1482
bfb7748a 1483to
9d67150a 1484
1485 optimize=' '
1486
1487then propagate your changes with B<sh Configure -S> and rebuild
1488with B<make depend; make>.
1489
4bbc1586 1490=item Missing functions and Undefined symbols
9d67150a 1491
4bbc1586
AD
1492If the build of miniperl fails with a long list of missing functions or
1493undefined symbols, check the libs variable in the config.sh file. It
1494should look something like
1495
1496 libs='-lsocket -lnsl -ldl -lm -lc'
1497
1498The exact libraries will vary from system to system, but you typically
1499need to include at least the math library -lm. Normally, Configure
1500will suggest the correct defaults. If the libs variable is empty, you
1501need to start all over again. Run
1502
1503 make distclean
1504
1505and start from the very beginning. This time, unless you are sure of
1506what you are doing, accept the default list of libraries suggested by
1507Configure.
1508
1509If the libs variable looks correct, you might have the
1510L<"nm extraction"> problem discussed above.
1511
1512If you stil have missing routines or undefined symbols, you probably
1513need to add some library or other, or you need to undefine some feature
1514that Configure thought was there but is defective or incomplete. If
1515you used a hint file, see if it has any relevant advice. You can also
1516look through through config.h for likely suspects.
8e07c86e 1517
1ec51d55 1518=item toke.c
8e07c86e 1519
1ec51d55
CS
1520Some compilers will not compile or optimize the larger files (such as
1521toke.c) without some extra switches to use larger jump offsets or
1522allocate larger internal tables. You can customize the switches for
1523each file in cflags. It's okay to insert rules for specific files into
1524makefile since a default rule only takes effect in the absence of a
8e07c86e
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1525specific rule.
1526
7f678428 1527=item Missing dbmclose
8e07c86e 1528
c3edaffb 1529SCO prior to 3.2.4 may be missing dbmclose(). An upgrade to 3.2.4
1530that includes libdbm.nfs (which includes dbmclose()) may be available.
8e07c86e 1531
f3d9a6ba 1532=item Note (probably harmless): No library found for -lsomething
7f678428 1533
1534If you see such a message during the building of an extension, but
1535the extension passes its tests anyway (see L<"make test"> below),
1536then don't worry about the warning message. The extension
1537Makefile.PL goes looking for various libraries needed on various
aa689395 1538systems; few systems will need all the possible libraries listed.
74b7c41f
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1539Most users will see warnings for the ones they don't have. The
1540phrase 'probably harmless' is intended to reassure you that nothing
1541unusual is happening, and the build process is continuing.
7f678428 1542
1543On the other hand, if you are building GDBM_File and you get the
1544message
1545
f3d9a6ba 1546 Note (probably harmless): No library found for -lgdbm
7f678428 1547
1548then it's likely you're going to run into trouble somewhere along
1549the line, since it's hard to see how you can use the GDBM_File
1550extension without the -lgdbm library.
1551
1552It is true that, in principle, Configure could have figured all of
1553this out, but Configure and the extension building process are not
1554quite that tightly coordinated.
1555
aa689395 1556=item sh: ar: not found
1557
1558This is a message from your shell telling you that the command 'ar'
1559was not found. You need to check your PATH environment variable to
1560make sure that it includes the directory with the 'ar' command. This
1ec51d55 1561is a common problem on Solaris, where 'ar' is in the /usr/ccs/bin
aa689395 1562directory.
1563
1564=item db-recno failure on tests 51, 53 and 55
1565
1566Old versions of the DB library (including the DB library which comes
1567with FreeBSD 2.1) had broken handling of recno databases with modified
1568bval settings. Upgrade your DB library or OS.
1569
6087ac44
JH
1570=item Bad arg length for semctl, is XX, should be ZZZ
1571
11906ba0 1572If you get this error message from the ext/IPC/SysV/t/sem test, your System
6087ac44
JH
1573V IPC may be broken. The XX typically is 20, and that is what ZZZ
1574also should be. Consider upgrading your OS, or reconfiguring your OS
1575to include the System V semaphores.
1576
11906ba0 1577=item ext/IPC/SysV/t/sem........semget: No space left on device
220f3621
GS
1578
1579Either your account or the whole system has run out of semaphores. Or
1580both. Either list the semaphores with "ipcs" and remove the unneeded
1581ones (which ones these are depends on your system and applications)
1582with "ipcrm -s SEMAPHORE_ID_HERE" or configure more semaphores to your
1583system.
1584
d6baa268
JH
1585=item GNU binutils
1586
1587If you mix GNU binutils (nm, ld, ar) with equivalent vendor-supplied
1588tools you may be in for some trouble. For example creating archives
1589with an old GNU 'ar' and then using a new current vendor-supplied 'ld'
1590may lead into linking problems. Either recompile your GNU binutils
1591under your current operating system release, or modify your PATH not
1592to include the GNU utils before running Configure, or specify the
1593vendor-supplied utilities explicitly to Configure, for example by
1594Configure -Dar=/bin/ar.
1595
16dc217a
GS
1596=item THIS PACKAGE SEEMS TO BE INCOMPLETE
1597
1598The F<Configure> program has not been able to find all the files which
1599make up the complete Perl distribution. You may have a damaged source
1600archive file (in which case you may also have seen messages such as
1601C<gzip: stdin: unexpected end of file> and C<tar: Unexpected EOF on
1602archive file>), or you may have obtained a structurally-sound but
1603incomplete archive. In either case, try downloading again from the
1604official site named at the start of this document. If you do find
1605that any site is carrying a corrupted or incomplete source code
1606archive, please report it to the site's maintainer.
1607
16dc217a
GS
1608=item invalid token: ##
1609
ce80d64e
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1610You are using a non-ANSI-compliant C compiler. To compile Perl, you
1611need to use a compiler that supports ANSI C. If there is a README
1612file for your system, it may have further details on your compiler
1613options.
16dc217a 1614
1ec51d55 1615=item Miscellaneous
8e07c86e 1616
7df75831 1617Some additional things that have been reported:
8e07c86e
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1618
1619Genix may need to use libc rather than libc_s, or #undef VARARGS.
1620
1621NCR Tower 32 (OS 2.01.01) may need -W2,-Sl,2000 and #undef MKDIR.
1622
9ede5bc8 1623UTS may need one or more of -K or -g, and undef LSTAT.
8e07c86e 1624
11906ba0 1625FreeBSD can fail the ext/IPC/SysV/t/sem.t test if SysV IPC has not been
5cda700b 1626configured in the kernel. Perl tries to detect this, though, and
ce80d64e 1627you will get a message telling you what to do.
6087ac44 1628
6c8d78fb
HS
1629Building Perl on a system that has also BIND (headers and libraries)
1630installed may run into troubles because BIND installs its own netdb.h
1631and socket.h, which may not agree with the operating system's ideas of
1632the same files. Similarly, including -lbind may conflict with libc's
1633view of the world. You may have to tweak -Dlocincpth and -Dloclibpth
1634to avoid the BIND.
1635
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1636=back
1637
58a21a9b
JH
1638=head2 Cross-compilation
1639
e7a3c61b
JH
1640Perl can be cross-compiled. It is just not trivial, cross-compilation
1641rarely is. Perl is routinely cross-compiled for many platforms (as of
1642June 2005 at least PocketPC aka WinCE, Open Zaurus, EPOC, Symbian, and
1643the IBM OS/400). These platforms are known as the B<target> platforms,
1644while the systems where the compilation takes place are the B<host>
1645platforms.
1646
1647What makes the situation difficult is that first of all,
1648cross-compilation environments vary significantly in how they are set
1649up and used, and secondly because the primary way of configuring Perl
1650(using the rather large Unix-tool-dependent Configure script) is not
1651awfully well suited for cross-compilation. However, starting from
1652version 5.8.0, the Configure script also knows one way of supporting
1653cross-compilation support, please keep reading.
1654
1655See the following files for more information about compiling Perl for
1656the particular platforms:
1657
1658=over 4
1659
1660=item WinCE/PocketPC
1661
75472953 1662README.ce
e7a3c61b
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1663
1664=item Open Zaurus
1665
1666Cross/README
1667
1668=item EPOC
1669
1670README.epoc
1671
1672=item Symbian
1673
1674README.symbian
1675
1676=item OS/400
1677
1678README.os400
1679
1680=back
1681
1682Packaging and transferring either the core Perl modules or CPAN
1683modules to the target platform is also left up to the each
1684cross-compilation environment. Often the cross-compilation target
1685platforms are somewhat limited in diskspace: see the section
1686L<Minimizing the Perl installation> to learn more of the minimal set
1687of files required for a functional Perl installation.
1688
1689For some cross-compilation environments the Configure option
1690C<-Dinstallprefix=...> might be handy, see L<Changing the installation
1691directory>.
1692
1693About the cross-compilation support of Configure: what is known to
1694work is running Configure in a cross-compilation environment and
1695building the miniperl executable. What is known not to work is
1696building the perl executable because that would require building
1697extensions: Dynaloader statically and File::Glob dynamically, for
1698extensions one needs MakeMaker and MakeMaker is not yet
1699cross-compilation aware, and neither is the main Makefile.
1700
1701The cross-compilation setup of Configure has successfully been used in
1702at least two Linux cross-compilation environments. The setups were
1703both such that the host system was Intel Linux with a gcc built for
1704cross-compiling into ARM Linux, and there was a SSH connection to the
1705target system.
1706
1707To run Configure in cross-compilation mode the basic switch that
1708has to be used is C<-Dusecrosscompile>.
58a21a9b
JH
1709
1710 sh ./Configure -des -Dusecrosscompile -D...
1711
1712This will make the cpp symbol USE_CROSS_COMPILE and the %Config
b0f06652
VK
1713symbol C<usecrosscompile> available, and C<xconfig.h> will be used
1714for cross-compilation.
58a21a9b
JH
1715
1716During the Configure and build, certain helper scripts will be created
1717into the Cross/ subdirectory. The scripts are used to execute a
1718cross-compiled executable, and to transfer files to and from the
1719target host. The execution scripts are named F<run-*> and the
1720transfer scripts F<to-*> and F<from-*>. The part after the dash is
1721the method to use for remote execution and transfer: by default the
1722methods are B<ssh> and B<scp>, thus making the scripts F<run-ssh>,
1723F<to-scp>, and F<from-scp>.
1724
1725To configure the scripts for a target host and a directory (in which
1726the execution will happen and which is to and from where the transfer
1727happens), supply Configure with
1728
1729 -Dtargethost=so.me.ho.st -Dtargetdir=/tar/get/dir
1730
1731The targethost is what e.g. ssh will use as the hostname, the targetdir
93bc48fa
JH
1732must exist (the scripts won't create it), the targetdir defaults to /tmp.
1733You can also specify a username to use for ssh/rsh logins
58a21a9b
JH
1734
1735 -Dtargetuser=luser
1736
1737but in case you don't, "root" will be used.
1738
93bc48fa
JH
1739Because this is a cross-compilation effort, you will also need to specify
1740which target environment and which compilation environment to use.
1741This includes the compiler, the header files, and the libraries.
1742In the below we use the usual settings for the iPAQ cross-compilation
1743environment:
58a21a9b
JH
1744
1745 -Dtargetarch=arm-linux
1746 -Dcc=arm-linux-gcc
1747 -Dusrinc=/skiff/local/arm-linux/include
1748 -Dincpth=/skiff/local/arm-linux/include
1749 -Dlibpth=/skiff/local/arm-linux/lib
1750
1751If the name of the C<cc> has the usual GNU C semantics for cross
1752compilers, that is, CPU-OS-gcc, the names of the C<ar>, C<nm>, and
1753C<ranlib> will also be automatically chosen to be CPU-OS-ar and so on.
93bc48fa
JH
1754(The C<ld> requires more thought and will be chosen later by Configure
1755as appropriate.) Also, in this case the incpth, libpth, and usrinc
1756will be guessed by Configure (unless explicitly set to something else,
1757in which case Configure's guesses with be appended).
58a21a9b
JH
1758
1759In addition to the default execution/transfer methods you can also
1760choose B<rsh> for execution, and B<rcp> or B<cp> for transfer,
1761for example:
1762
1763 -Dtargetrun=rsh -Dtargetto=rcp -Dtargetfrom=cp
1764
1765Putting it all together:
1766
1767 sh ./Configure -des -Dusecrosscompile \
93bc48fa
JH
1768 -Dtargethost=so.me.ho.st \
1769 -Dtargetdir=/tar/get/dir \
58a21a9b
JH
1770 -Dtargetuser=root \
1771 -Dtargetarch=arm-linux \
1772 -Dcc=arm-linux-gcc \
1773 -Dusrinc=/skiff/local/arm-linux/include \
1774 -Dincpth=/skiff/local/arm-linux/include \
1775 -Dlibpth=/skiff/local/arm-linux/lib \
1776 -D...
1777
e7a3c61b 1778or if you are happy with the defaults:
93bc48fa
JH
1779
1780 sh ./Configure -des -Dusecrosscompile \
1781 -Dtargethost=so.me.ho.st \
1782 -Dcc=arm-linux-gcc \
1783 -D...
1784
e7a3c61b
JH
1785Another example where the cross-compiler has been installed under
1786F</usr/local/arm/2.95.5>:
1787
1788 sh ./Configure -des -Dusecrosscompile \
1789 -Dtargethost=so.me.ho.st \
1790 -Dcc=/usr/local/arm/2.95.5/bin/arm-linux-gcc \
1791 -Dincpth=/usr/local/arm/2.95.5/include \
1792 -Dusrinc=/usr/local/arm/2.95.5/include \
1793 -Dlibpth=/usr/local/arm/2.95.5/lib
1794
8e07c86e
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1795=head1 make test
1796
d6baa268
JH
1797This will run the regression tests on the perl you just made. If
1798'make test' doesn't say "All tests successful" then something went
1799wrong. See the file t/README in the t subdirectory.
84902520 1800
84902520 1801Note that you can't run the tests in background if this disables
fb73857a 1802opening of /dev/tty. You can use 'make test-notty' in that case but
1803a few tty tests will be skipped.
c3edaffb 1804
c4f23d77
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1805=head2 What if make test doesn't work?
1806
1ec51d55
CS
1807If make test bombs out, just cd to the t directory and run ./TEST
1808by hand to see if it makes any difference. If individual tests
c3edaffb 1809bomb, you can run them by hand, e.g.,
8e07c86e 1810
785aa5e3 1811 cd t ; ./perl -MTestInit op/groups.t
8e07c86e 1812
aa689395 1813Another way to get more detailed information about failed tests and
1ec51d55 1814individual subtests is to cd to the t directory and run
aa689395 1815
785aa5e3 1816 cd t ; ./perl harness <list of tests>
aa689395 1817
fb73857a 1818(this assumes that most basic tests succeed, since harness uses
785aa5e3
RGS
1819complicated constructs). If no list of tests is provided, harness
1820will run all tests.
10c7e831 1821
fb73857a 1822You should also read the individual tests to see if there are any helpful
10c7e831
JH
1823comments that apply to your system. You may also need to setup your
1824shared library path if you get errors like:
1825
1826 /sbin/loader: Fatal Error: cannot map libperl.so
1827
1828See L</"Building a shared Perl library"> earlier in this document.
c3edaffb 1829
c4f23d77
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1830=over 4
1831
1832=item locale
1833
1ec51d55 1834Note: One possible reason for errors is that some external programs
c07a80fd 1835may be broken due to the combination of your environment and the way
785aa5e3 1836'make test' exercises them. For example, this may happen if you have
1ec51d55
CS
1837one or more of these environment variables set: LC_ALL LC_CTYPE
1838LC_COLLATE LANG. In some versions of UNIX, the non-English locales
e57fd563 1839are known to cause programs to exhibit mysterious errors.
1840
1841If you have any of the above environment variables set, please try
aa689395 1842
1843 setenv LC_ALL C
1844
1845(for C shell) or
1846
1847 LC_ALL=C;export LC_ALL
1848
1ec51d55
CS
1849for Bourne or Korn shell) from the command line and then retry
1850make test. If the tests then succeed, you may have a broken program that
aa689395 1851is confusing the testing. Please run the troublesome test by hand as
e57fd563 1852shown above and see whether you can locate the program. Look for
1ec51d55
CS
1853things like: exec, `backquoted command`, system, open("|...") or
1854open("...|"). All these mean that Perl is trying to run some
e57fd563 1855external program.
eed2e782 1856
0740bb5b
AD
1857=item Timing problems
1858
c29923ff
JH
1859Several tests in the test suite check timing functions, such as
1860sleep(), and see if they return in a reasonable amount of time.
9341413f
JH
1861If your system is quite busy and doesn't respond quickly enough,
1862these tests might fail. If possible, try running the tests again
1863with the system under a lighter load. These timing-sensitive
1864and load-sensitive tests include F<t/op/alarm.t>,
3831a787
NC
1865F<ext/Time-HiRes/t/HiRes.t>, F<ext/threads-shared/t/waithires.t>,
1866F<ext/threads-shared/t/stress.t>, F<lib/Benchmark.t>,
9341413f 1867F<lib/Memoize/t/expmod_t.t>, and F<lib/Memoize/t/speed.t>.
0740bb5b 1868
f89caa8d
RGS
1869You might also experience some failures in F<t/op/stat.t> if you build
1870perl on an NFS filesystem, if the remote clock and the system clock are
1871different.
1872
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1873=item Out of memory
1874
1875On some systems, particularly those with smaller amounts of RAM, some
1876of the tests in t/op/pat.t may fail with an "Out of memory" message.
7970f296
GS
1877For example, on my SparcStation IPC with 12 MB of RAM, in perl5.5.670,
1878test 85 will fail if run under either t/TEST or t/harness.
c4f23d77
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1879
1880Try stopping other jobs on the system and then running the test by itself:
1881
785aa5e3 1882 cd t; ./perl -MTestInit op/pat.t
c4f23d77
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1883
1884to see if you have any better luck. If your perl still fails this
1885test, it does not necessarily mean you have a broken perl. This test
1886tries to exercise the regular expression subsystem quite thoroughly,
1887and may well be far more demanding than your normal usage.
1888
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1889=item libgcc_s.so.1: cannot open shared object file
1890
1891This message has been reported on gcc-3.2.3 and earlier installed with
1892a non-standard prefix. Setting the LD_LIBRARY_PATH environment variable
1893(or equivalent) to include gcc's lib/ directory with the libgcc_s.so.1
1894shared library should fix the problem.
1895
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1896=item Failures from lib/File/Temp/t/security saying "system possibly insecure"
1897
1898First, such warnings are not necessarily serious or indicative of a
1899real security threat. That being said, they bear investigating.
1900
1901Note that each of the tests is run twice. The first time is in the
1902directory returned by File::Spec->tmpdir() (often /tmp on Unix
1903systems), and the second time in the directory from which the test was
1904run (usually the 't' directory, if the test was run as part of 'make
1905test').
1906
1907The tests may fail for the following reasons:
1908
1909(1) If the directory the tests are being run in is owned by somebody
1910other than the user running the tests, or by root (uid 0).
1911
1912This failure can happen if the Perl source code distribution is
1913unpacked in such a way that the user ids in the distribution package
1914are used as-is. Some tar programs do this.
1915
1916(2) If the directory the tests are being run in is writable by group or
1917by others, and there is no sticky bit set for the directory. (With
1918UNIX/POSIX semantics, write access to a directory means the right to
1919add or remove files in that directory. The 'sticky bit' is a feature
1920used in some UNIXes to give extra protection to files: if the bit is
1921set for a directory, no one but the owner (or root) can remove that
1922file even if the permissions would otherwise allow file removal by
1923others.)
1924
1925This failure may or may not be a real problem: it depends on the
1926permissions policy used on this particular system. This failure can
1927also happen if the system either doesn't support the sticky bit (this
1928is the case with many non-UNIX platforms: in principle File::Temp
1929should know about these platforms and skip the tests), or if the system
1930supports the sticky bit but for some reason or reasons it is not being
1931used. This is, for example, the case with HP-UX: as of HP-UX release
193211.00, the sticky bit is very much supported, but HP-UX doesn't use it
1933on its /tmp directory as shipped. Also, as with the permissions, some
1934local policy might dictate that the stickiness is not used.
781948c1 1935
b2b23189
JH
1936(3) If the system supports the POSIX 'chown giveaway' feature and if
1937any of the parent directories of the temporary file back to the root
1938directory are 'unsafe', using the definitions given above in (1) and
4f76e5ba
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1939(2). For Unix systems, this is usually not an issue if you are
1940building on a local disk. See the documentation for the File::Temp
1941module for more information about 'chown giveaway'.
781948c1
JH
1942
1943See the documentation for the File::Temp module for more information
4f76e5ba 1944about the various security aspects of temporary files.
781948c1 1945
c4f23d77
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1946=back
1947
8e07c86e
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1948=head1 make install
1949
1950This will put perl into the public directory you specified to
1ec51d55 1951Configure; by default this is /usr/local/bin. It will also try
8e07c86e 1952to put the man pages in a reasonable place. It will not nroff the man
aa689395 1953pages, however. You may need to be root to run B<make install>. If you
ce80d64e
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1954are not root, you must still have permission to install into the directories
1955in question and you should ignore any messages about chown not working.
1956
1957If "make install" just says "`install' is up to date" or something
1958similar, you may be on a case-insensitive filesystems such as Mac's HFS+,
1959and you should say "make install-all". (This confusion is brought to you
1960by the Perl distribution having a file called INSTALL.)
8e07c86e 1961
dd64f1c3
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1962=head2 Installing perl under different names
1963
1964If you want to install perl under a name other than "perl" (for example,
1965when installing perl with special features enabled, such as debugging),
1966indicate the alternate name on the "make install" line, such as:
1967
1968 make install PERLNAME=myperl
1969
beb13193 1970You can separately change the base used for versioned names (like
be8498a1 1971"perl5.8.9") by setting PERLNAME_VERBASE, like
beb13193
RS
1972
1973 make install PERLNAME=perl5 PERLNAME_VERBASE=perl
1974
5cda700b
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1975This can be useful if you have to install perl as "perl5" (e.g. to
1976avoid conflicts with an ancient version in /usr/bin supplied by your vendor).
be8498a1 1977Without this the versioned binary would be called "perl55.8.8".
beb13193 1978
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1979=head2 Installing perl under a different directory
1980
1981You can install perl under a different destination directory by using
1982the DESTDIR variable during C<make install>, with a command like
1983
1984 make install DESTDIR=/tmp/perl5
1985
1986DESTDIR is automatically prepended to all the installation paths. See
7df75831 1987the example in L<"DESTDIR"> above.
ce80d64e 1988
dd64f1c3
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1989=head2 Installed files
1990
8e07c86e
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1991If you want to see exactly what will happen without installing
1992anything, you can run
4633a7c4 1993
8e07c86e
AD
1994 ./perl installperl -n
1995 ./perl installman -n
1996
1ec51d55 1997make install will install the following:
8e07c86e 1998
d56c5707
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1999 binaries
2000
8e07c86e 2001 perl,
be8498a1 2002 perl5.n.n where 5.n.n is the current release number. This
8e07c86e
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2003 will be a link to perl.
2004 suidperl,
be8498a1 2005 sperl5.n.n If you requested setuid emulation.
8e07c86e 2006 a2p awk-to-perl translator
d56c5707
JH
2007
2008 scripts
2009
73d6d1b0
RGS
2010 cppstdin This is used by the deprecated switch perl -P, if
2011 your cc -E can't read from stdin.
8e07c86e 2012 c2ph, pstruct Scripts for handling C structures in header files.
73d6d1b0
RGS
2013 config_data Manage Module::Build-like module configuration
2014 corelist Shows versions of modules that come with different
2015 versions of perl
2016 cpan The CPAN shell
2017 cpan2dist The CPANPLUS distribution creator
2018 cpanp The CPANPLUS shell
2019 cpanp-run-perl An helper for cpanp
f5b5f377 2020 dprofpp Perl code profiler post-processor
73d6d1b0 2021 enc2xs Encoding module generator
8e07c86e 2022 find2perl find-to-perl translator
aa689395 2023 h2ph Extract constants and simple macros from C headers
8e07c86e 2024 h2xs Converts C .h header files to Perl extensions.
73d6d1b0
RGS
2025 instmodsh A shell to examine installed modules.
2026 libnetcfg Configure libnet.
24b3df7f 2027 perlbug Tool to report bugs in Perl.
8e07c86e 2028 perldoc Tool to read perl's pod documentation.
73d6d1b0
RGS
2029 perlivp Perl Installation Verification Procedure
2030 piconv A Perl implementation of the encoding conversion
2031 utility iconv
aa689395 2032 pl2pm Convert Perl 4 .pl files to Perl 5 .pm modules
8e07c86e 2033 pod2html, Converters from perl's pod documentation format
aa689395 2034 pod2latex, to other useful formats.
d56c5707
JH
2035 pod2man,
2036 pod2text,
d56c5707 2037 pod2usage
73d6d1b0
RGS
2038 podchecker POD syntax checker
2039 podselect Prints sections of POD documentation
2040 prove A command-line tool for running tests
2041 psed A Perl implementation of sed
2042 ptar A Perl implementation of tar
2043 ptardiff A diff for tar archives
2044 s2p sed-to-perl translator
2045 shasum A tool to print or check SHA checksums
aa689395 2046 splain Describe Perl warnings and errors
73d6d1b0 2047 xsubpp Compiler to convert Perl XS code into C code
8e07c86e 2048
d56c5707
JH
2049 library files
2050
2051 in $privlib and $archlib specified to
8e07c86e 2052 Configure, usually under /usr/local/lib/perl5/.
d56c5707
JH
2053
2054 documentation
2055
d6baa268
JH
2056 man pages in $man1dir, usually /usr/local/man/man1.
2057 module man
2058 pages in $man3dir, usually /usr/local/man/man3.
8e07c86e
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2059 pod/*.pod in $privlib/pod/.
2060
33cceb07 2061installperl will also create the directories listed above
d6baa268 2062in L<"Installation Directories">.
4633a7c4 2063
d56c5707 2064Perl's *.h header files and the libperl library are also installed
d6baa268 2065under $archlib so that any user may later build new modules, run the
56c6f531
JH
2066optional Perl compiler, or embed the perl interpreter into another
2067program even if the Perl source is no longer available.
8e07c86e 2068
33cceb07
RGS
2069=head2 Installing only version-specific parts
2070
d56c5707
JH
2071Sometimes you only want to install the version-specific parts of the perl
2072installation. For example, you may wish to install a newer version of
33cceb07 2073perl alongside an already installed production version without
d56c5707
JH
2074disabling installation of new modules for the production version.
2075To only install the version-specific parts of the perl installation, run
2076
2077 Configure -Dversiononly
2078
2079or answer 'y' to the appropriate Configure prompt. Alternatively,
2080you can just manually run
2081
2082 ./perl installperl -v
2083
2084and skip installman altogether.
33cceb07 2085
d56c5707
JH
2086See also L<"Maintaining completely separate versions"> for another
2087approach.
2088
f4ce0e6d
RGS
2089=head1 cd /usr/include; h2ph *.h sys/*.h
2090
2091Some perl scripts need to be able to obtain information from the
2092system header files. This command will convert the most commonly used
2093header files in /usr/include into files that can be easily interpreted
2094by perl. These files will be placed in the architecture-dependent
2095library ($archlib) directory you specified to Configure.
2096
2097Note: Due to differences in the C and perl languages, the conversion
2098of the header files is not perfect. You will probably have to
2099hand-edit some of the converted files to get them to parse correctly.
2100For example, h2ph breaks spectacularly on type casting and certain
2101structures.
2102
2103=head1 installhtml --help
2104
2105Some sites may wish to make perl documentation available in HTML
2106format. The installhtml utility can be used to convert pod
2107documentation into linked HTML files and install them.
2108
2109Currently, the supplied ./installhtml script does not make use of the
2110html Configure variables. This should be fixed in a future release.
2111
2112The following command-line is an example of one used to convert
2113perl documentation:
2114
2115 ./installhtml \
2116 --podroot=. \
2117 --podpath=lib:ext:pod:vms \
2118 --recurse \
2119 --htmldir=/perl/nmanual \
2120 --htmlroot=/perl/nmanual \
2121 --splithead=pod/perlipc \
2122 --splititem=pod/perlfunc \
2123 --libpods=perlfunc:perlguts:perlvar:perlrun:perlop \
2124 --verbose
2125
2126See the documentation in installhtml for more details. It can take
2127many minutes to execute a large installation and you should expect to
2128see warnings like "no title", "unexpected directive" and "cannot
2129resolve" as the files are processed. We are aware of these problems
2130(and would welcome patches for them).
2131
2132You may find it helpful to run installhtml twice. That should reduce
2133the number of "cannot resolve" warnings.
2134
2135=head1 cd pod && make tex && (process the latex files)
2136
2137Some sites may also wish to make the documentation in the pod/ directory
2138available in TeX format. Type
2139
2140 (cd pod && make tex && <process the latex files>)
2141
2142=head1 Starting all over again
2143
2144If you wish to re-build perl from the same build directory, you should
2145clean it out with the command
2146
2147 make distclean
2148
2149or
2150
2151 make realclean
2152
2153The only difference between the two is that make distclean also removes
2154your old config.sh and Policy.sh files.
2155
2156If you are upgrading from a previous version of perl, or if you
2157change systems or compilers or make other significant changes, or if
2158you are experiencing difficulties building perl, you should not re-use
2159your old config.sh.
2160
2161If your reason to reuse your old config.sh is to save your particular
2162installation choices, then you can probably achieve the same effect by
2163using the Policy.sh file. See the section on L<"Site-wide Policy
2164settings"> above.
2165
ff52061e
RGS
2166=head1 Reporting Problems
2167
2168Wherever possible please use the perlbug tool supplied with this Perl
2169to report problems, as it automatically includes summary configuration
2170information about your perl, which may help us track down problems far
2171more quickly. But first you should read the advice in this file,
2172carefully re-read the error message and check the relevant manual pages
2173on your system, as these may help you find an immediate solution. If
2174you are not sure whether what you are seeing is a bug, you can send a
2175message describing the problem to the comp.lang.perl.misc newsgroup to
2176get advice.
2177
2178The perlbug tool is installed along with perl, so after you have
2179completed C<make install> it should be possible to run it with plain
2180C<perlbug>. If the install fails, or you want to report problems with
2181C<make test> without installing perl, then you can use C<make nok> to
2182run perlbug to report the problem, or run it by hand from this source
2183directory with C<./perl -Ilib utils/perlbug>
2184
2185If the build fails too early to run perlbug uninstalled, then please
2186B<run> the C<./myconfig> shell script, and mail its output along with
2187an accurate description of your problem to perlbug@perl.org
2188
2189If Configure itself fails, and does not generate a config.sh file
2190(needed to run C<./myconfig>), then please mail perlbug@perl.org the
2191description of how Configure fails along with details of your system
2192- for example the output from running C<uname -a>
2193
2194Please try to make your message brief but clear. Brief, clear bug
2195reports tend to get answered more quickly. Please don't worry if your
2196written English is not great - what matters is how well you describe
2197the important technical details of the problem you have encountered,
2198not whether your grammar and spelling is flawless.
2199
2200Trim out unnecessary information. Do not include large files (such as
2201config.sh or a complete Configure or make log) unless absolutely
2202necessary. Do not include a complete transcript of your build
2203session. Just include the failing commands, the relevant error
2204messages, and whatever preceding commands are necessary to give the
2205appropriate context. Plain text should usually be sufficient--fancy
2206attachments or encodings may actually reduce the number of people who
2207read your message. Your message will get relayed to over 400
2208subscribers around the world so please try to keep it brief but clear.
2209
5acb7768
NC
2210If the bug you are reporting has security implications, which make it
2211inappropriate to send to a publicly archived mailing list, then please send
2212it to perl5-security-report@perl.org. This points to a closed subscription
2213unarchived mailing list, which includes all the core committers, who be able
2214to help assess the impact of issues, figure out a resolution, and help
2215co-ordinate the release of patches to mitigate or fix the problem across all
2216platforms on which Perl is supported. Please only use this address for security
2217issues in the Perl core, not for modules independently distributed on CPAN.
2218
ff52061e
RGS
2219If you are unsure what makes a good bug report please read "How to
2220report Bugs Effectively" by Simon Tatham:
2221http://www.chiark.greenend.org.uk/~sgtatham/bugs.html
2222
7df75831 2223=head1 Coexistence with earlier versions of perl 5
4633a7c4 2224
fdd3cf50 2225Perl 5.10 is not binary compatible with earlier versions of Perl.
cc65bb49 2226In other words, you will have to recompile your XS modules.
14eee2f1 2227
693762b4 2228In general, you can usually safely upgrade from one version of Perl (e.g.
33cceb07
RGS
22295.X.Y) to another similar minor version (e.g. 5.X.(Y+1))) without
2230re-compiling all of your extensions. You can also safely leave the old
2231version around in case the new version causes you problems for some reason.
693762b4 2232
be8498a1
RGS
2233Usually, most extensions will probably not need to be recompiled to be
2234used with a newer version of Perl. Here is how it is supposed to work.
ce80d64e 2235(These examples assume you accept all the Configure defaults.)
693762b4 2236
33cceb07
RGS
2237Suppose you already have version 5.8.7 installed. The directories
2238searched by 5.8.7 are typically like:
d6baa268 2239
33cceb07
RGS
2240 /usr/local/lib/perl5/5.8.7/$archname
2241 /usr/local/lib/perl5/5.8.7
2242 /usr/local/lib/perl5/site_perl/5.8.7/$archname
2243 /usr/local/lib/perl5/site_perl/5.8.7
d6baa268 2244
33cceb07
RGS
2245Now, suppose you install version 5.8.8. The directories
2246searched by version 5.8.8 will be:
d6baa268 2247
33cceb07
RGS
2248 /usr/local/lib/perl5/5.8.8/$archname
2249 /usr/local/lib/perl5/5.8.8
2250 /usr/local/lib/perl5/site_perl/5.8.8/$archname
2251 /usr/local/lib/perl5/site_perl/5.8.8
d6baa268 2252
33cceb07
RGS
2253 /usr/local/lib/perl5/site_perl/5.8.7/$archname
2254 /usr/local/lib/perl5/site_perl/5.8.7
c42e3e15 2255 /usr/local/lib/perl5/site_perl/
bfb7748a 2256
c42e3e15 2257Notice the last three entries -- Perl understands the default structure
d6baa268 2258of the $sitelib directories and will look back in older, compatible
33cceb07
RGS
2259directories. This way, modules installed under 5.8.7 will continue
2260to be usable by 5.8.7 but will also accessible to 5.8.8. Further,
d6baa268 2261suppose that you upgrade a module to one which requires features
33cceb07
RGS
2262present only in 5.8.8. That new module will get installed into
2263/usr/local/lib/perl5/site_perl/5.8.8 and will be available to 5.8.8,
2264but will not interfere with the 5.8.7 version.
bfb7748a 2265
c42e3e15 2266The last entry, /usr/local/lib/perl5/site_perl/, is there so that
fe23a901 22675.6.0 and above will look for 5.004-era pure perl modules.
d6baa268 2268
33cceb07
RGS
2269Lastly, suppose you now install 5.10.0, which is not binary compatible
2270with 5.8.x. The directories searched by 5.10.0 (if you don't change the
fe23a901
RF
2271Configure defaults) will be:
2272
33cceb07
RGS
2273 /usr/local/lib/perl5/5.10.0/$archname
2274 /usr/local/lib/perl5/5.10.0
2275 /usr/local/lib/perl5/site_perl/5.10.0/$archname
2276 /usr/local/lib/perl5/site_perl/5.10.0
d6baa268 2277
33cceb07 2278 /usr/local/lib/perl5/site_perl/5.8.8
d6baa268 2279
33cceb07 2280 /usr/local/lib/perl5/site_perl/5.8.7
fe23a901 2281
d6baa268 2282 /usr/local/lib/perl5/site_perl/
bfb7748a 2283
cc65bb49
AD
2284Note that the earlier $archname entries are now gone, but pure perl
2285modules from earlier versions will still be found.
2286
0a08c020
GS
2287This way, you can choose to share compatible extensions, but also upgrade
2288to a newer version of an extension that may be incompatible with earlier
2289versions, without breaking the earlier versions' installations.
693762b4
AD
2290
2291=head2 Maintaining completely separate versions
4633a7c4 2292
1ec51d55 2293Many users prefer to keep all versions of perl in completely
d6baa268 2294separate directories. This guarantees that an update to one version
0a08c020
GS
2295won't interfere with another version. (The defaults guarantee this for
2296libraries after 5.6.0, but not for executables. TODO?) One convenient
2297way to do this is by using a separate prefix for each version, such as
d52d4e46 2298
33cceb07 2299 sh Configure -Dprefix=/opt/perl5.10.0
d52d4e46 2300
33cceb07 2301and adding /opt/perl5.10.0/bin to the shell PATH variable. Such users
d52d4e46 2302may also wish to add a symbolic link /usr/local/bin/perl so that
2303scripts can still start with #!/usr/local/bin/perl.
2304
693762b4 2305Others might share a common directory for maintenance sub-versions
33cceb07 2306(e.g. 5.10 for all 5.10.x versions), but change directory with
693762b4
AD
2307each major version.
2308
6877a1cf
AD
2309If you are installing a development subversion, you probably ought to
2310seriously consider using a separate directory, since development
2311subversions may not have all the compatibility wrinkles ironed out
2312yet.
2313
dd3196cd 2314=head2 Upgrading from 5.8.x or earlier
693762b4 2315
dd3196cd
RGS
2316B<Perl 5.10.0 is binary incompatible with Perl 5.8.x and any earlier
2317Perl release.> Perl modules having binary parts
e655887d 2318(meaning that a C compiler is used) will have to be recompiled to be
dd3196cd
RGS
2319used with 5.10.0. If you find you do need to rebuild an extension with
23205.10.0, you may safely do so without disturbing the older
7df75831 2321installations. (See L<"Coexistence with earlier versions of perl 5">
e655887d 2322above.)
c42e3e15
GS
2323
2324See your installed copy of the perllocal.pod file for a (possibly
2325incomplete) list of locally installed modules. Note that you want
cc65bb49 2326perllocal.pod, not perllocale.pod, for installed module information.
693762b4 2327
8ebf57cf
JH
2328=head1 Minimizing the Perl installation
2329
2330The following section is meant for people worrying about squeezing the
2331Perl installation into minimal systems (for example when installing
2332operating systems, or in really small filesystems).
2333
c8214fdf 2334Leaving out as many extensions as possible is an obvious way:
5cda700b
AD
2335Encode, with its big conversion tables, consumes a lot of
2336space. On the other hand, you cannot throw away everything. The
2337Fcntl module is pretty essential. If you need to do network
c8214fdf
JH
2338programming, you'll appreciate the Socket module, and so forth: it all
2339depends on what do you need to do.
2340
8ebf57cf
JH
2341In the following we offer two different slimmed down installation
2342recipes. They are informative, not normative: the choice of files
2343depends on what you need.
2344
2345Firstly, the bare minimum to run this script
2346
2347 use strict;
2348 use warnings;
2349 foreach my $f (</*>) {
2350 print("$f\n");
2351 }
2352
bfe08c74 2353in Linux is as follows (under $Config{prefix}):
8ebf57cf
JH
2354
2355 ./bin/perl
bfe08c74
RGS
2356 ./lib/perl5/5.9.3/strict.pm
2357 ./lib/perl5/5.9.3/warnings.pm
2358 ./lib/perl5/5.9.3/i686-linux/File/Glob.pm
2359 ./lib/perl5/5.9.3/i686-linux/XSLoader.pm
2360 ./lib/perl5/5.9.3/i686-linux/auto/File/Glob/Glob.so
8ebf57cf
JH
2361
2362Secondly, Debian perl-base package contains the following files,
bfe08c74 2363size about 1.9MB in its i386 version:
8ebf57cf 2364
bfe08c74
RGS
2365 /usr/bin/perl
2366 /usr/bin/perl5.8.4
2367 /usr/lib/perl/5.8
2368 /usr/lib/perl/5.8.4/B.pm
2369 /usr/lib/perl/5.8.4/B/Deparse.pm
2370 /usr/lib/perl/5.8.4/Config.pm
2371 /usr/lib/perl/5.8.4/Cwd.pm
2372 /usr/lib/perl/5.8.4/Data/Dumper.pm
2373 /usr/lib/perl/5.8.4/DynaLoader.pm
2374 /usr/lib/perl/5.8.4/Errno.pm
2375 /usr/lib/perl/5.8.4/Fcntl.pm
2376 /usr/lib/perl/5.8.4/File/Glob.pm
2377 /usr/lib/perl/5.8.4/IO.pm
2378 /usr/lib/perl/5.8.4/IO/File.pm
2379 /usr/lib/perl/5.8.4/IO/Handle.pm
2380 /usr/lib/perl/5.8.4/IO/Pipe.pm
2381 /usr/lib/perl/5.8.4/IO/Seekable.pm
2382 /usr/lib/perl/5.8.4/IO/Select.pm
2383 /usr/lib/perl/5.8.4/IO/Socket.pm
2384 /usr/lib/perl/5.8.4/POSIX.pm
2385 /usr/lib/perl/5.8.4/Socket.pm
2386 /usr/lib/perl/5.8.4/XSLoader.pm
2387 /usr/lib/perl/5.8.4/auto/Cwd/Cwd.bs
2388 /usr/lib/perl/5.8.4/auto/Cwd/Cwd.so
2389 /usr/lib/perl/5.8.4/auto/Data/Dumper/Dumper.bs
2390 /usr/lib/perl/5.8.4/auto/Data/Dumper/Dumper.so
2391 /usr/lib/perl/5.8.4/auto/DynaLoader/DynaLoader.a
2392 /usr/lib/perl/5.8.4/auto/DynaLoader/autosplit.ix
2393 /usr/lib/perl/5.8.4/auto/DynaLoader/dl_expandspec.al
2394 /usr/lib/perl/5.8.4/auto/DynaLoader/dl_find_symbol_anywhere.al
2395 /usr/lib/perl/5.8.4/auto/DynaLoader/dl_findfile.al
2396 /usr/lib/perl/5.8.4/auto/DynaLoader/extralibs.ld
2397 /usr/lib/perl/5.8.4/auto/Fcntl/Fcntl.bs
2398 /usr/lib/perl/5.8.4/auto/Fcntl/Fcntl.so
2399 /usr/lib/perl/5.8.4/auto/File/Glob/Glob.bs
2400 /usr/lib/perl/5.8.4/auto/File/Glob/Glob.so
2401 /usr/lib/perl/5.8.4/auto/IO/IO.bs
2402 /usr/lib/perl/5.8.4/auto/IO/IO.so
2403 /usr/lib/perl/5.8.4/auto/POSIX/POSIX.bs
2404 /usr/lib/perl/5.8.4/auto/POSIX/POSIX.so
2405 /usr/lib/perl/5.8.4/auto/POSIX/autosplit.ix
2406 /usr/lib/perl/5.8.4/auto/POSIX/load_imports.al
2407 /usr/lib/perl/5.8.4/auto/Socket/Socket.bs
2408 /usr/lib/perl/5.8.4/auto/Socket/Socket.so
2409 /usr/lib/perl/5.8.4/lib.pm
2410 /usr/lib/perl/5.8.4/re.pm
2411 /usr/share/doc/perl-base
8ebf57cf 2412 /usr/share/doc/perl/AUTHORS.gz
bfe08c74
RGS
2413 /usr/share/doc/perl/Documentation
2414 /usr/share/doc/perl/README.Debian.gz
8ebf57cf 2415 /usr/share/doc/perl/changelog.Debian.gz
bfe08c74 2416 /usr/share/doc/perl/copyright
8ebf57cf 2417 /usr/share/man/man1/perl.1.gz
bfe08c74
RGS
2418 /usr/share/perl/5.8
2419 /usr/share/perl/5.8.4/AutoLoader.pm
2420 /usr/share/perl/5.8.4/Carp.pm
2421 /usr/share/perl/5.8.4/Carp/Heavy.pm
2422 /usr/share/perl/5.8.4/Exporter.pm
2423 /usr/share/perl/5.8.4/Exporter/Heavy.pm
2424 /usr/share/perl/5.8.4/File/Spec.pm
2425 /usr/share/perl/5.8.4/File/Spec/Unix.pm
2426 /usr/share/perl/5.8.4/FileHandle.pm
2427 /usr/share/perl/5.8.4/Getopt/Long.pm
2428 /usr/share/perl/5.8.4/IO/Socket/INET.pm
2429 /usr/share/perl/5.8.4/IO/Socket/UNIX.pm
2430 /usr/share/perl/5.8.4/IPC/Open2.pm
2431 /usr/share/perl/5.8.4/IPC/Open3.pm
2432 /usr/share/perl/5.8.4/List/Util.pm
2433 /usr/share/perl/5.8.4/Scalar/Util.pm
2434 /usr/share/perl/5.8.4/SelectSaver.pm
2435 /usr/share/perl/5.8.4/Symbol.pm
2436 /usr/share/perl/5.8.4/Text/ParseWords.pm
2437 /usr/share/perl/5.8.4/Text/Tabs.pm
2438 /usr/share/perl/5.8.4/Text/Wrap.pm
2439 /usr/share/perl/5.8.4/attributes.pm
2440 /usr/share/perl/5.8.4/base.pm
2441 /usr/share/perl/5.8.4/bytes.pm
2442 /usr/share/perl/5.8.4/bytes_heavy.pl
2443 /usr/share/perl/5.8.4/constant.pm
2444 /usr/share/perl/5.8.4/fields.pm
2445 /usr/share/perl/5.8.4/integer.pm
2446 /usr/share/perl/5.8.4/locale.pm
2447 /usr/share/perl/5.8.4/overload.pm
2448 /usr/share/perl/5.8.4/strict.pm
2449 /usr/share/perl/5.8.4/utf8.pm
2450 /usr/share/perl/5.8.4/utf8_heavy.pl
2451 /usr/share/perl/5.8.4/vars.pm
2452 /usr/share/perl/5.8.4/warnings.pm
2453 /usr/share/perl/5.8.4/warnings/register.pm
8ebf57cf 2454
e7a3c61b
JH
2455A nice trick to find out the minimal set of Perl library files you will
2456need to run a Perl program is
2457
a0a8d9d3 2458 perl -e 'do "prog.pl"; END { print "$_\n" for sort keys %INC }'
e7a3c61b
JH
2459
2460(this will not find libraries required in runtime, unfortunately, but
2461it's a minimal set) and if you want to find out all the files you can
2462use something like the below
2463
2464 strace perl -le 'do "x.pl"' 2>&1 | perl -nle '/^open\(\"(.+?)"/ && print $1'
2465
2466(The 'strace' is Linux-specific, other similar utilities include 'truss'
2467and 'ktrace'.)
2468
c19ccd8c
RGS
2469=head2 C<-DNO_MATHOMS>
2470
2471If you configure perl with C<-Accflags=-DNO_MATHOMS>, the functions from
2472F<mathoms.c> will not be compiled in. Those functions are no longer used
2473by perl itself; for source compatibility reasons, though, they weren't
2474completely removed.
2475
8e07c86e
AD
2476=head1 DOCUMENTATION
2477
bfb7748a
AD
2478Read the manual entries before running perl. The main documentation
2479is in the pod/ subdirectory and should have been installed during the
8e07c86e 2480build process. Type B<man perl> to get started. Alternatively, you
bfb7748a
AD
2481can type B<perldoc perl> to use the supplied perldoc script. This is
2482sometimes useful for finding things in the library modules.
8e07c86e
AD
2483
2484=head1 AUTHOR
2485
bfb7748a
AD
2486Original author: Andy Dougherty doughera@lafayette.edu , borrowing very
2487heavily from the original README by Larry Wall, with lots of helpful
2488feedback and additions from the perl5-porters@perl.org folks.
fb73857a 2489
f5b3b617
AD
2490If you have problems, corrections, or questions, please see
2491L<"Reporting Problems"> above.
2492
2493=head1 REDISTRIBUTION
2494
2495This document is part of the Perl package and may be distributed under
d6baa268 2496the same terms as perl itself, with the following additional request:
f5b3b617 2497If you are distributing a modified version of perl (perhaps as part of
d6baa268
JH
2498a larger package) please B<do> modify these installation instructions
2499and the contact information to match your distribution.