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1If you read this file _as_is_, just ignore the equal signs on the left.
2This file is written in the POD format (see [.POD]PERLPOD.POD;1) which is
3specially designed to be readable as is.
fb73857a 4
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5=head1 NAME
6
7README.vms - Configuring, building, testing, and installing perl on VMS
8
9=head1 SYNOPSIS
10
11To configure, build, test, and install perl on VMS:
12
13 @ Configure
14 mms
15 mms test
16 mms install
17
18mmk may be used in place of mms in the last three steps.
19
20=head1 DESCRIPTION
21
22=head2 Important safety tip
97abc6ad 23
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24For best results, make sure you read the "Configuring the Perl Build",
25"Building Perl", and "Installing Perl" sections of this document before
26you build or install. Also please note other changes in the current
27release by having a look at L<perldelta/VMS>.
97abc6ad 28
b4bc034f 29Also note that, as of Perl version 5.005 and later, an ANSI C compliant
da80cd87 30compiler is required to build Perl. VAX C is I<not> ANSI compliant, as it
b4bc034f 31died a natural death some time before the standard was set. Therefore
1bc81404 32VAX C will not compile Perl 5.005 or later. We are sorry about that.
3bf5f72b 33
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34There have been no recent reports of builds using Gnu C, but latent
35(and most likely outdated) support for it is still present in various
36parts of the sources. Currently the HP (formerly Compaq, and even
37more formerly DEC) C compiler is the only viable alternative for
38building Perl.
39
40There is minimal support for HP C++ but this support is not complete;
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41if you get it working please write to the vmsperl list (for info see
42L</"Mailing Lists">).
3bf5f72b 43
b4bc034f 44
a83b6f46 45=head2 Introduction to Perl on VMS
fb73857a 46
47The VMS port of Perl is as functionally complete as any other Perl port
48(and as complete as the ports on some Unix systems). The Perl binaries
49provide all the Perl system calls that are either available under VMS or
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50reasonably emulated. There are some incompatibilities in process handling
51(e.g. the fork/exec model for creating subprocesses doesn't do what you
fb73857a 52might expect under Unix), mainly because VMS and Unix handle processes and
53sub-processes very differently.
54
b4bc034f 55There are still some unimplemented system functions, and of course we
fb73857a 56could use modules implementing useful VMS system services, so if you'd like
b4bc034f 57to lend a hand we'd love to have you. Join the Perl Porting Team Now!
fb73857a 58
a83b6f46 59=head2 Other required software for Compiling Perl on VMS
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60
61In addition to VMS and DCL you will need two things:
fb73857a 62
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63=over 4
64
65=item 1 A C compiler.
66
10019e56 67HP (formerly Compaq, more formerly DEC) C for VMS (VAX, Alpha, or Itanium).
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68Various ancient versions of DEC C had some caveats, so if you're using a
69version older than 7.x on Alpha or Itanium or 6.x on VAX, you may need to
70upgrade to get a successful build.
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71
72=item 2 A make tool.
73
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74HP's MMS may work, but MadGoat's free MMS analog MMK (available from
75http://www.kednos.com/kednos/Resources/MMK) has consistently worked
76better. Gnu Make might work, but it's been so long since anyone's tested
77it that we're not sure. MMK is free though, so go ahead and use that.
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78
79=back
80
a83b6f46 81=head2 Additional software that is optional for Perl on VMS
fb73857a 82
9f3f8d50 83You may also want to have on hand:
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84
85=over 4
86
da80cd87 87=item 1 GUNZIP/GZIP for VMS
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88
89A de-compressor for *.gz and *.tgz files available from a number
58979ab1 90of web/ftp sites and is distributed on the OpenVMS Freeware CD-ROM
10019e56 91from HP.
b4bc034f 92
10019e56 93 http://www.hp.com/go/openvms/freeware/
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94
95=item 2 VMS TAR
96
97For reading and writing unix tape archives (*.tar files). Vmstar is also
58979ab1 98available from a number of web/ftp sites and is distributed on the OpenVMS
10019e56 99Freeware CD-ROM from HP.
b4bc034f 100
10019e56 101 http://www.hp.com/go/openvms/freeware/
b4bc034f 102
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103Recent versions of VMS tar on ODS-5 volumes may extract tape archive
104files with ^. escaped periods in them. See below for further workarounds.
105
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106A port of GNU tar is also available as part of the GNV package:
107
ec55d5e4 108 http://h71000.www7.hp.com/opensource/gnv.html
10019e56 109
da80cd87 110=item 3 UNZIP for VMS
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111
112A combination decompressor and archive reader/writer for *.zip files.
113Unzip is available from a number of web/ftp sites.
114
adc5a9a5 115 http://www.info-zip.org/UnZip.html
10019e56 116 http://www.hp.com/go/openvms/freeware/
eb863851 117 ftp://ftp.process.com/vms-freeware/fileserv/
b4bc034f 118
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119=item 5 GNU PATCH and DIFFUTILS for VMS
120
121Patches to Perl are usually distributed as GNU unified or contextual diffs.
122Such patches are created by the GNU diff program (part of the diffutils
123distribution) and applied with GNU patch. VMS ports of these utilities are
124available here:
125
ec55d5e4 126 http://www.antinode.info/dec/sw/diffutils.html
10019e56 127 http://www.hp.com/go/openvms/freeware/
1bc81404 128
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129=back
130
9f3f8d50 131Please note that UNZIP and GUNZIP are not the same thing (they work with
b4bc034f 132different formats). Many of the useful files from CPAN (the Comprehensive
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133Perl Archive Network) are in *.tar.gz or *.tgz format (this includes copies
134of the source code for perl as well as modules and scripts that you may
135wish to add later) hence you probably want to have GUNZIP.EXE and
136VMSTAR.EXE on your VMS machine.
fb73857a 137
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138If you want to include socket support, you'll need a TCP/IP stack and either
139DEC C, or socket libraries. See the "Socket Support (optional)" topic
140for more details.
fb73857a 141
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142=head1 Unpacking the Perl source code
143
144You may need to set up a foreign symbol for the unpacking utility of choice.
145
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146As of version 5.10.0, Perl will still build and run on ODS-2 volumes,
147including on VAX, but there are a number of modules whose temporary
148files and tests are much happier residing on ODS-5 volumes. For
149example, CPANPLUS will fail most of its tests on an ODS-2 volume because
150it includes files with multiple dots that will have been converted to
151underscores and the tests will have difficulty finding them. So your
152best bet is to unpack the Perl source kit on an ODS-5 volume using
153recent versions of vmstar (e.g. V3.4 or later). Contrary to advice
154provided with previous versions of Perl, do I<not> use the ODS-2
155compatability qualifier. Instead, use a command like the following:
156
6f15df47 157 vmstar /extract/verbose perl-V^.XI^.I.tar
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158
159or:
160
6f15df47 161 vmstar -xvf perl-5^.11^.1.tar
d83fac45 162
718752a5 163Then rename the top-level source directory like so:
d83fac45 164
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165 set security/protection=(o:rwed) perl-5^.11^.1.dir
166 rename perl-5^.11^.1.dir perl-5_11_1.dir
d83fac45 167
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168The reason for this last step is that while filenames with multiple dots
169are generally supported by Perl on VMS, I<directory> names with multiple
170dots are a special case with special problems because the dot is the
171traditional directory delimiter on VMS. Rudimentary support for
172multi-dot directory names is available, but some of the oldest and most
173essential parts of Perl (such as searching for and loading library
174modules) do not yet fully support the ODS-5 caret-escape syntax.
d83fac45 175
b4bc034f 176=head1 Configuring the Perl build
fb73857a 177
97abc6ad 178To configure perl (a necessary first step), issue the command
fb73857a 179
b4bc034f 180 @ Configure
fb73857a 181
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182from the top of an unpacked perl source directory. You will be asked a
183series of questions, and the answers to them (along with the capabilities
184of your C compiler and network stack) will determine how perl is custom
185built for your machine.
fb73857a 186
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187If you have any symbols or logical names in your environment that may
188interfere with the build or regression testing of perl then configure.com
189will try to warn you about them. If a logical name is causing
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190you trouble but is in an LNM table that you do not have write access to
191then try defining your own to a harmless equivalence string in a table
192such that it is resolved before the other (e.g. if TMP is defined in the
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193SYSTEM table then try DEFINE TMP "NL:" or somesuch in your process table)
194otherwise simply deassign the dangerous logical names. The potentially
195troublesome logicals and symbols are:
7bb57f25 196
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197 COMP "LOGICAL"
198 EXT "LOGICAL"
199 FOO "LOGICAL"
200 LIB "LOGICAL"
201 LIST "LOGICAL"
202 MIME "LOGICAL"
203 POSIX "LOGICAL"
204 SYS "LOGICAL"
205 T "LOGICAL"
206 THREAD "LOGICAL"
207 THREADS "LOGICAL"
208 TIME "LOGICAL"
209 TMP "LOGICAL"
210 UNICODE "LOGICAL"
211 UTIL "LOGICAL"
212 TEST "SYMBOL"
fb73857a 213
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214As a handy shortcut, the command:
215
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216 @ Configure "-des"
217
218(note the quotation marks and case) will choose reasonable defaults
219automatically (it takes DEC C over Gnu C, DEC C sockets over SOCKETSHR
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220sockets, and either over no sockets). Some options can be given
221explicitly on the command line; the following example specifies a
222non-default location for where Perl will be installed:
223
224 @ Configure "-d" "-Dprefix=dka100:[utils.perl5.]"
225
dab31494 226Note that the installation location would be by default where you unpacked
fe05d1a7 227the source with a "_ROOT." appended. For example if you unpacked the perl
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228source into:
229
230 DKA200:[PERL-5_10_2...]
231
adc5a9a5 232Then the PERL_SETUP.COM that gets written out by CONFIGURE.COM will
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233try to DEFINE your installation PERL_ROOT to be:
234
fe05d1a7 235 DKA200:[PERL-5_10_2_ROOT.]
dab31494 236
1bc81404 237More help with configure.com is available from:
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238
239 @ Configure "-h"
240
241See the "Changing compile-time options (optional)" section below to learn
242even more details about how to influence the outcome of the important
243configuration step. If you find yourself reconfiguring and rebuilding
244then be sure to also follow the advice in the "Cleaning up and starting
245fresh (optional)" and the checklist of items in the "CAVEATS" sections
246below.
247
a83b6f46 248=head2 Changing compile-time options (optional) for Perl on VMS
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249
250Most of the user definable features of Perl are enabled or disabled in
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251configure.com, which processes the hints file config_h.SH. There is
252code in there to Do The Right Thing, but that may end up being the
253wrong thing for you. Make sure you understand what you are doing since
254inappropriate changes to configure.com or config_h.SH can render perl
255unbuildable; odds are that there's nothing in there you'll need to
256change.
b4bc034f 257
a83b6f46 258=head2 Socket Support (optional) for Perl on VMS
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259
260Perl includes a number of functions for IP sockets, which are available if
261you choose to compile Perl with socket support. Since IP networking is an
262optional addition to VMS, there are several different IP stacks available.
263How well integrated they are into the system depends on the stack, your
264version of VMS, and the version of your C compiler.
265
17d4810c 266The default solution available is to use the socket routines built into DEC
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267C. Which routines are available depend on the version of VMS you're
268running, and require proper UCX emulation by your TCP/IP vendor.
269Relatively current versions of Multinet, TCPWare, Pathway, and UCX all
270provide the required libraries--check your manuals or release notes to see
271if your version is new enough.
272
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273The other solution uses the SOCKETSHR library. Before VAX/VMS 5.5-2 it was
274the most portable solution. The SOCKETSHR library has not been maintained
275since VAX/VMS 5.5-2, and it is not known if will even compile with the ANSI
276C that Perl currently requires. It remains an option for historical reasons,
277just in case someone might find it useful.
278
279In combination with either UCX or NetLib, this supported all the major TCP
280stacks (Multinet, Pathways, TCPWare, UCX, and CMU) on all versions of VMS
281Perl ran on up to VAX/VMS 6.2 and Alpha VMS 1.5 with all the compilers on
282both VAX and Alpha. The portion of the socket interface was also consistent
283across versions of VMS and C compilers.
284
285It has a problem with UDP sockets when used with Multinet, though, so you
286should be aware of that.
287
288As of VAX/VMS 5.5-2 and later, CMU is the only TCP/IP program that requires
289socketshr, and the sources have been lost to the most recent CMU bug fixes,
290so CMU is limited to OpenVMS/VAX 6.2 or earlier, which is the last release
291that binaries for the last released patches are known to exist.
292
293There is currently no official web site for downloading either CMU or
294SOCKETSHR; however, copies may be found in the DECUS archives.
295
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296=head1 Building Perl
297
298The configuration script will print out, at the very end, the MMS or MMK
299command you need to compile perl. Issue it (exactly as printed) to start
300the build.
97abc6ad 301
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302Once you issue your MMS or MMK command, sit back and wait. Perl should
303compile and link without a problem. If a problem does occur check the
304"CAVEATS" section of this document. If that does not help send some
305mail to the VMSPERL mailing list. Instructions are in the "Mailing Lists"
306section of this document.
97abc6ad 307
b4bc034f 308=head1 Testing Perl
fb73857a 309
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310Once Perl has built cleanly you need to test it to make sure things work.
311This step is very important since there are always things that can go wrong
312somehow and yield a dysfunctional Perl for you.
fb73857a 313
314Testing is very easy, though, as there's a full test suite in the perl
da80cd87 315distribution. To run the tests, enter the I<exact> MMS line you used to
fb73857a 316compile Perl and add the word "test" to the end, like this:
317
b4bc034f 318If the compile command was:
fb73857a 319
b4bc034f 320 MMS
fb73857a 321
b4bc034f 322then the test command ought to be:
fb73857a 323
b4bc034f 324 MMS test
fb73857a 325
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326MMS (or MMK) will run all the tests. This may take some time, as there are
327a lot of tests. If any tests fail, there will be a note made on-screen.
328At the end of all the tests, a summary of the tests, the number passed and
329failed, and the time taken will be displayed.
fb73857a 330
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331The test driver invoked via MMS TEST has a DCL wrapper ([.VMS]TEST.COM) that
332downgrades privileges to NETMBX, TMPMBX for the duration of the test run,
333and then restores them to their prior state upon completion of testing.
334This is done to ensure that the tests run in a private sandbox and can do no
335harm to your system even in the unlikely event something goes badly wrong in
336one of the test scripts while running the tests from a privileged account.
337A side effect of this safety precaution is that the account used to run the
338test suite must be the owner of the directory tree in which Perl has been
339built; otherwise the manipulations of temporary files and directories
340attempted by some of the tests will fail.
341
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342If any tests fail, it means something is wrong with Perl, or at least
343with the particular module or feature that reported failure. If the test suite
fb73857a 344hangs (some tests can take upwards of two or three minutes, or more if
9f3f8d50 345you're on an especially slow machine, depending on your machine speed, so
da80cd87 346don't be hasty), then the test I<after> the last one displayed failed. Don't
fb73857a 347install Perl unless you're confident that you're OK. Regardless of how
348confident you are, make a bug report to the VMSPerl mailing list.
349
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350If one or more tests fail, you can get more information on the failure by
351issuing this command sequence:
fb73857a 352
b4bc034f 353 @ [.VMS]TEST .typ "" "-v" [.subdir]test.T
fb73857a 354
355where ".typ" is the file type of the Perl images you just built (if you
356didn't do anything special, use .EXE), and "[.subdir]test.T" is the test
357that failed. For example, with a normal Perl build, if the test indicated
96d6186e 358that t/op/time failed, then you'd do this:
fb73857a 359
b4bc034f 360 @ [.VMS]TEST .EXE "" "-v" [.OP]TIME.T
fb73857a 361
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362Note that test names are reported in UNIX syntax and relative to the
363top-level build directory. When supplying them individually to the test
364driver, you can use either UNIX or VMS syntax, but you must give the path
365relative to the [.T] directory and you must also add the .T extension to the
366filename. So, for example if the test lib/Math/Trig fails, you would run:
367
368 @ [.VMS]TEST .EXE "" -"v" [-.lib.math]trig.t
369
fb73857a 370When you send in a bug report for failed tests, please include the output
371from this command, which is run from the main source directory:
372
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373 MCR []MINIPERL "-V"
374
375Note that -"V" really is a capital V in double quotes. This will dump out a
376couple of screens worth of configuration information, and can help us
377diagnose the problem. If (and only if) that did not work then try enclosing
378the output of:
379
380 MMS printconfig
fb73857a 381
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382If (and only if) that did not work then try enclosing the output of:
383
b4bc034f 384 @ [.vms]myconfig
fb73857a 385
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386You may also be asked to provide your C compiler version ("CC/VERSION NL:"
387with DEC C, "gcc --version" with GNU CC). To obtain the version of MMS or
388MMK you are running try "MMS/ident" or "MMK /ident". The GNU make version
389can be identified with "make --version".
390
a83b6f46 391=head2 Cleaning up and starting fresh (optional) installing Perl on VMS
fb73857a 392
393If you need to recompile from scratch, you have to make sure you clean up
da80cd87 394first. There is a procedure to do it--enter the I<exact> MMS line you used
b4bc034f 395to compile and add "realclean" at the end, like this:
fb73857a 396
b4bc034f 397if the compile command was:
fb73857a 398
b4bc034f 399 MMS
fb73857a 400
b4bc034f 401then the cleanup command ought to be:
fb73857a 402
b4bc034f 403 MMS realclean
fb73857a 404
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405If you do not do this things may behave erratically during the subsequent
406rebuild attempt. They might not, too, so it is best to be sure and do it.
fb73857a 407
b4bc034f 408=head1 Installing Perl
fb73857a 409
410There are several steps you need to take to get Perl installed and
3a385817 411running.
fb73857a 412
a3ef2c6f 413=over 4
b4bc034f 414
a3ef2c6f 415=item 1
fb73857a 416
a3ef2c6f 417Check your default file protections with
fb73857a 418
a3ef2c6f 419 SHOW PROTECTION /DEFAULT
fb73857a 420
a3ef2c6f 421and adjust if necessary with SET PROTECTION=(code)/DEFAULT.
fb73857a 422
a3ef2c6f 423=item 2
3a385817 424
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425Decide where you want Perl to be installed (unless you have already done so
426by using the "prefix" configuration parameter -- see the example in the
427"Configuring the Perl build" section).
b4bc034f 428
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429The DCL script PERL_SETUP.COM that is written by CONFIGURE.COM will help you
430with the definition of the PERL_ROOT and PERLSHR logical names and the PERL
431foreign command symbol. Take a look at PERL_SETUP.COM and modify it if you
432want to. The installation process will execute PERL_SETUP.COM and copy
433files to the directory tree pointed to by the PERL_ROOT logical name defined
434there, so make sure that you have write access to the parent directory of
435what will become the root of your Perl installation.
fb73857a 436
a3ef2c6f 437=item 3
b4bc034f 438
a3ef2c6f 439Run the install script via:
b4bc034f 440
a3ef2c6f 441 MMS install
b4bc034f 442
a3ef2c6f 443or
9f3f8d50 444
a3ef2c6f 445 MMK install
b4bc034f 446
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447If for some reason it complains about target INSTALL being up to date,
448throw a /FORCE switch on the MMS or MMK command.
b4bc034f 449
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450=back
451
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452Copy PERL_SETUP.COM to a place accessible to your perl users.
453
a3ef2c6f 454For example:
fb73857a 455
a3ef2c6f 456 COPY PERL_SETUP.COM SYS$LIBRARY:
b4bc034f 457
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458If you want to have everyone on the system have access to perl
459then add a line that reads
fb73857a 460
a3ef2c6f 461 $ @sys$library:perl_setup
491527d0 462
a3ef2c6f 463to SYS$MANAGER:SYLOGIN.COM.
85988417 464
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465Two alternatives to the foreign symbol would be to install PERL into
466DCLTABLES.EXE (Check out the section "Installing Perl into DCLTABLES
467(optional)" for more information), or put the image in a
468directory that's in your DCL$PATH (if you're using VMS V6.2 or higher).
85988417 469
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470An alternative to having PERL_SETUP.COM define the PERLSHR logical name
471is to simply copy it into the system shareable library directory with:
472
473 copy perl_root:[000000]perlshr.exe sys$share:
85988417 474
a3ef2c6f 475See also the "INSTALLing images (optional)" section.
491527d0 476
a83b6f46 477=head2 Installing Perl into DCLTABLES (optional) on VMS
fb73857a 478
9ef4b0a6 479Execute the following command file to define PERL as a DCL command.
b4bc034f 480You'll need CMKRNL privilege to install the new dcltables.exe.
fb73857a 481
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482 $ create perl.cld
483 !
484 ! modify to reflect location of your perl.exe
485 !
486 define verb perl
487 image perl_root:[000000]perl.exe
488 cliflags (foreign)
489 $!
490 $ set command perl /table=sys$common:[syslib]dcltables.exe -
491 /output=sys$common:[syslib]dcltables.exe
492 $ install replace sys$common:[syslib]dcltables.exe
493 $ exit
fb73857a 494
a83b6f46 495=head2 INSTALLing Perl images (optional) on VMS
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496
497On systems that are using perl quite a bit, and particularly those with
498minimal RAM, you can boost the performance of perl by INSTALLing it as
adc5a9a5 499a known image. PERLSHR.EXE is typically larger than 3000 blocks
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500and that is a reasonably large amount of IO to load each time perl is
501invoked.
502
503 INSTALL ADD PERLSHR/SHARE
b4bc034f 504 INSTALL ADD PERL/HEADER
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505
506should be enough for PERLSHR.EXE (/share implies /header and /open),
507while /HEADER should do for PERL.EXE (perl.exe is not a shared image).
508
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509If your code 'use's modules, check to see if there is a shareable image for
510them, too. In the base perl build, POSIX, IO, Fcntl, Opcode, SDBM_File,
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511DCLsym, and Stdio, and other extensions all have shared images that can be
512installed /SHARE.
9f3f8d50 513
b4bc034f 514How much of a win depends on your memory situation, but if you are firing
9f3f8d50 515off perl with any regularity (like more than once every 20 seconds or so)
b4bc034f 516it is probably beneficial to INSTALL at least portions of perl.
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517
518While there is code in perl to remove privileges as it runs you are advised
519to NOT INSTALL PERL.EXE with PRIVs!
fb73857a 520
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521=head2 Running h2ph to create perl header files (optional) on VMS
522
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523If using HP C, ensure that you have extracted loose versions of your
524compiler's header or *.H files. Be sure to check the contents of:
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525
526 SYS$LIBRARY:DECC$RTLDEF.TLB
527 SYS$LIBRARY:SYS$LIB_C.TLB
528 SYS$LIBRARY:SYS$STARLET_C.TLB
529
530etcetera.
531
532If using GNU cc then also check your GNU_CC:[000000...] tree for the locations
533of the GNU cc headers.
534
b4bc034f 535=head1 Reporting Bugs
fb73857a 536
537If you come across what you think might be a bug in Perl, please report
538it. There's a script in PERL_ROOT:[UTILS], perlbug, that walks you through
539the process of creating a bug report. This script includes details of your
540installation, and is very handy. Completed bug reports should go to
9f3f8d50 541perlbug@perl.com.
fb73857a 542
b4bc034f 543=head1 CAVEATS
fb73857a 544
545Probably the single biggest gotcha in compiling Perl is giving the wrong
da80cd87 546switches to MMS/MMK when you build. Use I<exactly> what the configure.com
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547script prints!
548
549The next big gotcha is directory depth. Perl can create directories four,
550five, or even six levels deep during the build, so you don't have to be
dab31494 551too deep to start to hit the RMS 8 level limit (for ODS 2 volumes which were
ec55d5e4 552common on versions of VMS prior to V7.2 and even with V7.3 on the VAX).
dab31494 553It is best to do:
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554
555 DEFINE/TRANS=(CONC,TERM) PERLSRC "disk:[dir.dir.dir.perldir.]"
556 SET DEFAULT PERLSRC:[000000]
557
558before building in cases where you have to unpack the distribution so deep
559(note the trailing period in the definition of PERLSRC). Perl modules
560from CPAN can be just as bad (or worse), so watch out for them, too. Perl's
561configuration script will warn if it thinks you are too deep (at least on
562a VAX or on Alpha versions of VMS prior to 7.2). But MakeMaker will not
563warn you if you start out building a module too deep in a directory.
564
d83fac45 565As noted above ODS-5 escape sequences such as ^. can break the perl
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566build. Solutions include renaming files and directories as needed
567when unpacking perl or CPAN modules on ODS-5 volumes.
d83fac45 568
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569Be sure that the process that you use to build perl has a PGFLQ greater
570than 100000. Be sure to have a correct local time zone to UTC offset
571defined (in seconds) in the logical name SYS$TIMEZONE_DIFFERENTIAL before
572running the regression test suite. The SYS$MANAGER:UTC$CONFIGURE_TDF.COM
573procedure will help you set that logical for your system but may require
574system privileges. For example, a location 5 hours west of UTC (such as
575the US East coast while not on daylight savings time) would have:
576
577 DEFINE SYS$TIMEZONE_DIFFERENTIAL "-18000"
578
579A final thing that causes trouble is leftover pieces from a failed
580build. If things go wrong make sure you do a "(MMK|MMS|make) realclean"
fb73857a 581before you rebuild.
582
a83b6f46 583=head2 GNU issues with Perl on VMS
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584
585It has been a while since the GNU utilities such as GCC or GNU make
586were used to build perl on VMS. Hence they may require a great deal
587of source code modification to work again.
588
b4bc034f 589 http://www.progis.de/
b4bc034f 590
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591=head2 Floating Point Considerations
592
593Prior to 5.8.0, Perl simply accepted the default floating point options of the
594C compiler, namely representing doubles with D_FLOAT on VAX and G_FLOAT on
595Alpha. Single precision floating point values are represented in F_FLOAT
596format when either D_FLOAT or G_FLOAT is in use for doubles. Beginning with
5975.8.0, Alpha builds now use IEEE floating point formats by default, which in
598VMS parlance are S_FLOAT for singles and T_FLOAT for doubles. IEEE is not
599available on VAX, so F_FLOAT and D_FLOAT remain the defaults for singles and
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600doubles respectively. Itanium builds have always used IEEE by default. The
601available non-default options are G_FLOAT on VAX and D_FLOAT or G_FLOAT on
602Alpha or Itanium.
e7948fac 603
da80cd87 604The use of IEEE on Alpha or Itanium introduces NaN, infinity, and denormalization
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605capabilities not available with D_FLOAT and G_FLOAT. When using one of those
606non-IEEE formats, silent underflow and overflow are emulated in the conversion
607of strings to numbers, but it is preferable to get the real thing by using
608IEEE where possible.
609
610Regardless of what floating point format you consider preferable, be aware
611that the choice may have an impact on compatibility with external libraries,
612such as database interfaces, and with existing data, such as data created with
613the C<pack> function and written to disk, or data stored via the Storable
614extension. For example, a C<pack("d", $foo)")> will create a D_FLOAT,
615G_FLOAT, or T_FLOAT depending on what your Perl was configured with. When
616written to disk, the value can only be retrieved later by a Perl configured
617with the same floating point option that was in effect when it was created.
618
619To obtain a non-IEEE build on Alpha, simply answer no to the "Use IEEE math?"
620question during the configuration. To obtain an option different from the C
621compiler default on either VAX or Alpha, put in the option that you want in
622answer to the "Any additional cc flags?" question. For example, to obtain a
623G_FLOAT build on VAX, put in C</FLOAT=G_FLOAT>.
624
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625=head1 Mailing Lists
626
627There are several mailing lists available to the Perl porter. For VMS
fb73857a 628specific issues (including both Perl questions and installation problems)
b4bc034f 629there is the VMSPERL mailing list. It is usually a low-volume (10-12
fb73857a 630messages a week) mailing list.
631
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632To subscribe, send a mail message to VMSPERL-SUBSCRIBE@PERL.ORG. The VMSPERL
633mailing list address is VMSPERL@PERL.ORG. Any mail sent there gets echoed
634to all subscribers of the list. There is a searchable archive of the list
635on the web at:
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636
637 http://www.xray.mpe.mpg.de/mailing-lists/vmsperl/
a83b6f46 638
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639To unsubscribe from VMSPERL send a message to VMSPERL-UNSUBSCRIBE@PERL.ORG.
640Be sure to do so from the subscribed account that you are canceling.
b4bc034f 641
a83b6f46 642=head2 Web sites for Perl on VMS
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643
644Vmsperl pages on the web include:
645
646 http://www.sidhe.org/vmsperl/index.html
468f45d5 647 http://www.cpan.org/modules/by-module/VMS/
60d9c7be 648 http://www.xray.mpe.mpg.de/mailing-lists/vmsperl/
adc5a9a5 649 http://www-ang.kfunigraz.ac.at/~binder/perl.html
60d9c7be 650 http://archive.develooper.com/vmsperl@perl.org/
10019e56 651 http://h71000.www7.hp.com/openvms/products/ips/apache/csws_modperl.html
fb73857a 652
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653=head1 SEE ALSO
654
655Perl information for users and programmers about the port of perl to VMS is
3bc8f799 656available from the [.POD]PERLVMS.POD file that gets installed as L<perlvms>.
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657For administrators the perlvms document also includes a detailed discussion
658of extending vmsperl with CPAN modules after Perl has been installed.
659
660=head1 AUTHORS
661
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662Originally by Charles Bailey bailey@newman.upenn.edu. See the git repository
663for history.
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664
665=head1 ACKNOWLEDGEMENTS
fb73857a 666
667A real big thanks needs to go to Charles Bailey
b4bc034f 668bailey@newman.upenn.edu, who is ultimately responsible for Perl 5.004
fb73857a 669running on VMS. Without him, nothing the rest of us have done would be at
670all important.
671
672There are, of course, far too many people involved in the porting and testing
673of Perl to mention everyone who deserves it, so please forgive us if we've
674missed someone. That said, special thanks are due to the following:
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675
676 Tim Adye T.J.Adye@rl.ac.uk
fb73857a 677 for the VMS emulations of getpw*()
b4bc034f 678 David Denholm denholm@conmat.phys.soton.ac.uk
fb73857a 679 for extensive testing and provision of pipe and SocketShr code,
b4bc034f 680 Mark Pizzolato mark@infocomm.com
fb73857a 681 for the getredirection() code
b4bc034f 682 Rich Salz rsalz@bbn.com
fb73857a 683 for readdir() and related routines
b4bc034f 684 Peter Prymmer pvhp@best.com
fb73857a 685 for extensive testing, as well as development work on
686 configuration and documentation for VMS Perl,
b4bc034f 687 Dan Sugalski dan@sidhe.org
fb73857a 688 for extensive contributions to recent version support,
689 development of VMS-specific extensions, and dissemination
690 of information about VMS Perl,
691 the Stanford Synchrotron Radiation Laboratory and the
692 Laboratory of Nuclear Studies at Cornell University for
9f3f8d50 693 the opportunity to test and develop for the AXP,
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694 John Hasstedt John.Hasstedt@sunysb.edu
695 for VAX VMS V7.2 support
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696 John Malmberg wb8tyw@qsl.net
697 for ODS-5 filename handling and other modernizations
b4bc034f 698
fb73857a 699and to the entire VMSperl group for useful advice and suggestions. In
700addition the perl5-porters deserve credit for their creativity and
701willingness to work with the VMS newcomers. Finally, the greatest debt of
b4bc034f 702gratitude is due to Larry Wall larry@wall.org, for having the ideas which
fb73857a 703have made our sleepless nights possible.
704
705Thanks,
706The VMSperl group
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707
708=cut
709