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. 4 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 23 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>. 28 29Also note that, as of Perl version 5.005 and later, an ANSI C compliant 30compiler is required to build Perl. VAX C is *not* ANSI compliant, as it 31died a natural death some time before the standard was set. Therefore 32VAX C will not compile Perl 5.005 or later. We are sorry about that. 33 34There have been no recent reports of builds using Gnu C, but latent 35(and most likely outdated) support for it is still present in various 36parts of the sources.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; 41if you get it working please write to the vmsperl list (for info see 42L</"Mailing Lists">). 43 44 45=head2 Introduction to Perl on VMS 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 50reasonably emulated. There are some incompatibilities in process handling 51(e.g. the fork/exec model for creating subprocesses doesn't do what you 52might expect under Unix), mainly because VMS and Unix handle processes and 53sub-processes very differently. 54 55There are still some unimplemented system functions, and of course we 56could use modules implementing useful VMS system services, so if you'd like 57to lend a hand we'd love to have you. Join the Perl Porting Team Now! 58 59There are issues with various versions of DEC C, so if you're not running a 60relatively modern version, check the "DEC C issues" section later on in this 61document. 62 63=head2 Other required software for Compiling Perl on VMS 64 65In addition to VMS and DCL you will need two things: 66 67=over 4 68 69=item 1 A C compiler. 70 71HP (formerly Compaq, more formerly DEC) C for VMS (VAX, Alpha, or Itanium). 72 73=item 2 A make tool. 74 75HP's MMS may work, but MadGoat's free MMS analog MMK (available from 76http://www.kednos.com/kednos/Resources/MMK) has consistently worked 77better. Gnu Make might work, but it's been so long since anyone's tested 78it that we're not sure. MMK is free though, so go ahead and use that. 79 80=back 81 82=head2 Additional software that is optional for Perl on VMS 83 84You may also want to have on hand: 85 86=over 4 87 88=item 1 GUNZIP/GZIP.EXE for VMS 89 90A de-compressor for *.gz and *.tgz files available from a number 91of web/ftp sites and is distributed on the OpenVMS Freeware CD-ROM 92from HP. 93 94 http://www.hp.com/go/openvms/freeware/ 95 http://www.crinoid.com/utils/ 96 97=item 2 VMS TAR 98 99For reading and writing unix tape archives (*.tar files). Vmstar is also 100available from a number of web/ftp sites and is distributed on the OpenVMS 101Freeware CD-ROM from HP. 102 103 http://www.hp.com/go/openvms/freeware/ 104 105Recent versions of VMS tar on ODS-5 volumes may extract tape archive 106files with ^. escaped periods in them. See below for further workarounds. 107 108A port of GNU tar is also available as part of the GNV package: 109 110 http://h71000.www7.hp.com/opensource/gnv.html 111 112=item 3 UNZIP.EXE for VMS 113 114A combination decompressor and archive reader/writer for *.zip files. 115Unzip is available from a number of web/ftp sites. 116 117 http://www.info-zip.org/UnZip.html 118 http://www.hp.com/go/openvms/freeware/ 119 ftp://ftp.hp.com/pub/openvms 120 ftp://ftp.process.com/vms-freeware/fileserv 121 122=item 4 MOST 123 124Most is an optional pager that is convenient to use with perldoc (unlike 125TYPE/PAGE, MOST can go forward and backwards in a document and supports 126regular expression searching). Most builds with the slang 127library on VMS. Most and slang are available from: 128 129 ftp://space.mit.edu/pub/davis/ 130 ftp://ftp.process.com/vms-freeware/narnia/ 131 132=item 5 GNU PATCH and DIFFUTILS for VMS 133 134Patches to Perl are usually distributed as GNU unified or contextual diffs. 135Such patches are created by the GNU diff program (part of the diffutils 136distribution) and applied with GNU patch. VMS ports of these utilities are 137available here: 138 139 http://www.antinode.info/dec/sw/diffutils.html 140 http://www.hp.com/go/openvms/freeware/ 141 142=back 143 144Please note that UNZIP and GUNZIP are not the same thing (they work with 145different formats). Many of the useful files from CPAN (the Comprehensive 146Perl Archive Network) are in *.tar.gz or *.tgz format (this includes copies 147of the source code for perl as well as modules and scripts that you may 148wish to add later) hence you probably want to have GUNZIP.EXE and 149VMSTAR.EXE on your VMS machine. 150 151If you want to include socket support, you'll need a TCP/IP stack and either 152DEC C, or socket libraries. See the "Socket Support (optional)" topic 153for more details. 154 155=head1 Unpacking the Perl source code 156 157You may need to set up a foreign symbol for the unpacking utility of choice. 158 159As of version 5.10.0, Perl will still build and run on ODS-2 volumes, 160including on VAX, but there are a number of modules whose temporary 161files and tests are much happier residing on ODS-5 volumes. For 162example, CPANPLUS will fail most of its tests on an ODS-2 volume because 163it includes files with multiple dots that will have been converted to 164underscores and the tests will have difficulty finding them. So your 165best bet is to unpack the Perl source kit on an ODS-5 volume using 166recent versions of vmstar (e.g. V3.4 or later). Contrary to advice 167provided with previous versions of Perl, do I<not> use the ODS-2 168compatability qualifier. Instead, use a command like the following: 169 170 vmstar /extract/verbose perl-V^.VIII^.III.tar 171 172or: 173 174 vmstar -xvf perl-5^.10^.1.tar 175 176Then rename the top-level source directory like so: 177 178 set security/protection=(o:rwed) perl-5^.10^.1.dir 179 rename perl-5^.10^.1.dir perl-5_10_1.dir 180 181The reason for this last step is that while filenames with multiple dots 182are generally supported by Perl on VMS, I<directory> names with multiple 183dots are a special case with special problems because the dot is the 184traditional directory delimiter on VMS. Rudimentary support for 185multi-dot directory names is available, but some of the oldest and most 186essential parts of Perl (such as searching for and loading library 187modules) do not yet fully support the ODS-5 caret-escape syntax. 188 189=head1 Configuring the Perl build 190 191To configure perl (a necessary first step), issue the command 192 193 @ Configure 194 195from the top of an unpacked perl source directory. You will be asked a 196series of questions, and the answers to them (along with the capabilities 197of your C compiler and network stack) will determine how perl is custom 198built for your machine. 199 200If you have multiple C compilers installed, you'll have your choice of 201which one to use. Various older versions of DEC C had some caveats, so if 202you're using a version older than 5.2, check the "DEC C Issues" section. 203 204If you have any symbols or logical names in your environment that may 205interfere with the build or regression testing of perl then configure.com 206will try to warn you about them. If a logical name is causing 207you trouble but is in an LNM table that you do not have write access to 208then try defining your own to a harmless equivalence string in a table 209such that it is resolved before the other (e.g. if TMP is defined in the 210SYSTEM table then try DEFINE TMP "NL:" or somesuch in your process table) 211otherwise simply deassign the dangerous logical names. The potentially 212troublesome logicals and symbols are: 213 214 COMP "LOGICAL" 215 EXT "LOGICAL" 216 FOO "LOGICAL" 217 LIB "LOGICAL" 218 LIST "LOGICAL" 219 MIME "LOGICAL" 220 POSIX "LOGICAL" 221 SYS "LOGICAL" 222 T "LOGICAL" 223 THREAD "LOGICAL" 224 THREADS "LOGICAL" 225 TIME "LOGICAL" 226 TMP "LOGICAL" 227 UNICODE "LOGICAL" 228 UTIL "LOGICAL" 229 TEST "SYMBOL" 230 231As a handy shortcut, the command: 232 233 @ Configure "-des" 234 235(note the quotation marks and case) will choose reasonable defaults 236automatically (it takes DEC C over Gnu C, DEC C sockets over SOCKETSHR 237sockets, and either over no sockets). Some options can be given 238explicitly on the command line; the following example specifies a 239non-default location for where Perl will be installed: 240 241 @ Configure "-d" "-Dprefix=dka100:[utils.perl5.]" 242 243Note that the installation location would be by default where you unpacked 244the source with a "_ROOT." appended. For example if you unpacked the perl 245source into: 246 247 DKA200:[PERL-5_10_2...] 248 249Then the PERL_SETUP.COM that gets written out by CONFIGURE.COM will 250try to DEFINE your installation PERL_ROOT to be: 251 252 DKA200:[PERL-5_10_2_ROOT.] 253 254More help with configure.com is available from: 255 256 @ Configure "-h" 257 258See the "Changing compile-time options (optional)" section below to learn 259even more details about how to influence the outcome of the important 260configuration step. If you find yourself reconfiguring and rebuilding 261then be sure to also follow the advice in the "Cleaning up and starting 262fresh (optional)" and the checklist of items in the "CAVEATS" sections 263below. 264 265=head2 Changing compile-time options (optional) for Perl on VMS 266 267Most of the user definable features of Perl are enabled or disabled in 268configure.com, which processes the hints file config_h.SH. There is 269code in there to Do The Right Thing, but that may end up being the 270wrong thing for you. Make sure you understand what you are doing since 271inappropriate changes to configure.com or config_h.SH can render perl 272unbuildable; odds are that there's nothing in there you'll need to 273change. 274 275=head2 Socket Support (optional) for Perl on VMS 276 277Perl includes a number of functions for IP sockets, which are available if 278you choose to compile Perl with socket support. Since IP networking is an 279optional addition to VMS, there are several different IP stacks available. 280How well integrated they are into the system depends on the stack, your 281version of VMS, and the version of your C compiler. 282 283The default solution available is to use the socket routines built into DEC 284C. Which routines are available depend on the version of VMS you're 285running, and require proper UCX emulation by your TCP/IP vendor. 286Relatively current versions of Multinet, TCPWare, Pathway, and UCX all 287provide the required libraries--check your manuals or release notes to see 288if your version is new enough. 289 290The other solution uses the SOCKETSHR library. Before VAX/VMS 5.5-2 it was 291the most portable solution. The SOCKETSHR library has not been maintained 292since VAX/VMS 5.5-2, and it is not known if will even compile with the ANSI 293C that Perl currently requires. It remains an option for historical reasons, 294just in case someone might find it useful. 295 296In combination with either UCX or NetLib, this supported all the major TCP 297stacks (Multinet, Pathways, TCPWare, UCX, and CMU) on all versions of VMS 298Perl ran on up to VAX/VMS 6.2 and Alpha VMS 1.5 with all the compilers on 299both VAX and Alpha. The portion of the socket interface was also consistent 300across versions of VMS and C compilers. 301 302It has a problem with UDP sockets when used with Multinet, though, so you 303should be aware of that. 304 305As of VAX/VMS 5.5-2 and later, CMU is the only TCP/IP program that requires 306socketshr, and the sources have been lost to the most recent CMU bug fixes, 307so CMU is limited to OpenVMS/VAX 6.2 or earlier, which is the last release 308that binaries for the last released patches are known to exist. 309 310There is currently no official web site for downloading either CMU or 311SOCKETSHR; however, copies may be found in the DECUS archives. 312 313=head1 Building Perl 314 315The configuration script will print out, at the very end, the MMS or MMK 316command you need to compile perl. Issue it (exactly as printed) to start 317the build. 318 319Once you issue your MMS or MMK command, sit back and wait. Perl should 320compile and link without a problem. If a problem does occur check the 321"CAVEATS" section of this document. If that does not help send some 322mail to the VMSPERL mailing list. Instructions are in the "Mailing Lists" 323section of this document. 324 325=head1 Testing Perl 326 327Once Perl has built cleanly you need to test it to make sure things work. 328This step is very important since there are always things that can go wrong 329somehow and yield a dysfunctional Perl for you. 330 331Testing is very easy, though, as there's a full test suite in the perl 332distribution. To run the tests, enter the *exact* MMS line you used to 333compile Perl and add the word "test" to the end, like this: 334 335If the compile command was: 336 337 MMS 338 339then the test command ought to be: 340 341 MMS test 342 343MMS (or MMK) will run all the tests. This may take some time, as there are 344a lot of tests. If any tests fail, there will be a note made on-screen. 345At the end of all the tests, a summary of the tests, the number passed and 346failed, and the time taken will be displayed. 347 348The test driver invoked via MMS TEST has a DCL wrapper ([.VMS]TEST.COM) that 349downgrades privileges to NETMBX, TMPMBX for the duration of the test run, 350and then restores them to their prior state upon completion of testing. 351This is done to ensure that the tests run in a private sandbox and can do no 352harm to your system even in the unlikely event something goes badly wrong in 353one of the test scripts while running the tests from a privileged account. 354A side effect of this safety precaution is that the account used to run the 355test suite must be the owner of the directory tree in which Perl has been 356built; otherwise the manipulations of temporary files and directories 357attempted by some of the tests will fail. 358 359If any tests fail, it means something is wrong with Perl, or at least 360with the particular module or feature that reported failure. If the test suite 361hangs (some tests can take upwards of two or three minutes, or more if 362you're on an especially slow machine, depending on your machine speed, so 363don't be hasty), then the test *after* the last one displayed failed. Don't 364install Perl unless you're confident that you're OK. Regardless of how 365confident you are, make a bug report to the VMSPerl mailing list. 366 367If one or more tests fail, you can get more information on the failure by 368issuing this command sequence: 369 370 @ [.VMS]TEST .typ "" "-v" [.subdir]test.T 371 372where ".typ" is the file type of the Perl images you just built (if you 373didn't do anything special, use .EXE), and "[.subdir]test.T" is the test 374that failed. For example, with a normal Perl build, if the test indicated 375that t/op/time failed, then you'd do this: 376 377 @ [.VMS]TEST .EXE "" "-v" [.OP]TIME.T 378 379Note that test names are reported in UNIX syntax and relative to the 380top-level build directory. When supplying them individually to the test 381driver, you can use either UNIX or VMS syntax, but you must give the path 382relative to the [.T] directory and you must also add the .T extension to the 383filename. So, for example if the test lib/Math/Trig fails, you would run: 384 385 @ [.VMS]TEST .EXE "" -"v" [-.lib.math]trig.t 386 387When you send in a bug report for failed tests, please include the output 388from this command, which is run from the main source directory: 389 390 MCR []MINIPERL "-V" 391 392Note that -"V" really is a capital V in double quotes. This will dump out a 393couple of screens worth of configuration information, and can help us 394diagnose the problem. If (and only if) that did not work then try enclosing 395the output of: 396 397 MMS printconfig 398 399If (and only if) that did not work then try enclosing the output of: 400 401 @ [.vms]myconfig 402 403You may also be asked to provide your C compiler version ("CC/VERSION NL:" 404with DEC C, "gcc --version" with GNU CC). To obtain the version of MMS or 405MMK you are running try "MMS/ident" or "MMK /ident". The GNU make version 406can be identified with "make --version". 407 408=head2 Cleaning up and starting fresh (optional) installing Perl on VMS 409 410If you need to recompile from scratch, you have to make sure you clean up 411first. There is a procedure to do it--enter the *exact* MMS line you used 412to compile and add "realclean" at the end, like this: 413 414if the compile command was: 415 416 MMS 417 418then the cleanup command ought to be: 419 420 MMS realclean 421 422If you do not do this things may behave erratically during the subsequent 423rebuild attempt. They might not, too, so it is best to be sure and do it. 424 425=head1 Installing Perl 426 427There are several steps you need to take to get Perl installed and 428running. 429 430=over 4 431 432=item 1 433 434Check your default file protections with 435 436 SHOW PROTECTION /DEFAULT 437 438and adjust if necessary with SET PROTECTION=(code)/DEFAULT. 439 440=item 2 441 442Decide where you want Perl to be installed (unless you have already done so 443by using the "prefix" configuration parameter -- see the example in the 444"Configuring the Perl build" section). 445 446The DCL script PERL_SETUP.COM that is written by CONFIGURE.COM will help you 447with the definition of the PERL_ROOT and PERLSHR logical names and the PERL 448foreign command symbol. Take a look at PERL_SETUP.COM and modify it if you 449want to. The installation process will execute PERL_SETUP.COM and copy 450files to the directory tree pointed to by the PERL_ROOT logical name defined 451there, so make sure that you have write access to the parent directory of 452what will become the root of your Perl installation. 453 454=item 3 455 456Run the install script via: 457 458 MMS install 459 460or 461 462 MMK install 463 464If for some reason it complains about target INSTALL being up to date, 465throw a /FORCE switch on the MMS or MMK command. 466 467=back 468 469Copy PERL_SETUP.COM to a place accessible to your perl users. 470 471For example: 472 473 COPY PERL_SETUP.COM SYS$LIBRARY: 474 475If you want to have everyone on the system have access to perl 476then add a line that reads 477 478 $ @sys$library:perl_setup 479 480to SYS$MANAGER:SYLOGIN.COM. 481 482Two alternatives to the foreign symbol would be to install PERL into 483DCLTABLES.EXE (Check out the section "Installing Perl into DCLTABLES 484(optional)" for more information), or put the image in a 485directory that's in your DCL$PATH (if you're using VMS V6.2 or higher). 486 487An alternative to having PERL_SETUP.COM define the PERLSHR logical name 488is to simply copy it into the system shareable library directory with: 489 490 copy perl_root:[000000]perlshr.exe sys$share: 491 492See also the "INSTALLing images (optional)" section. 493 494=head2 Installing Perl into DCLTABLES (optional) on VMS 495 496Execute the following command file to define PERL as a DCL command. 497You'll need CMKRNL privilege to install the new dcltables.exe. 498 499 $ create perl.cld 500 ! 501 ! modify to reflect location of your perl.exe 502 ! 503 define verb perl 504 image perl_root:[000000]perl.exe 505 cliflags (foreign) 506 $! 507 $ set command perl /table=sys$common:[syslib]dcltables.exe - 508 /output=sys$common:[syslib]dcltables.exe 509 $ install replace sys$common:[syslib]dcltables.exe 510 $ exit 511 512=head2 INSTALLing Perl images (optional) on VMS 513 514On systems that are using perl quite a bit, and particularly those with 515minimal RAM, you can boost the performance of perl by INSTALLing it as 516a known image. PERLSHR.EXE is typically larger than 3000 blocks 517and that is a reasonably large amount of IO to load each time perl is 518invoked. 519 520 INSTALL ADD PERLSHR/SHARE 521 INSTALL ADD PERL/HEADER 522 523should be enough for PERLSHR.EXE (/share implies /header and /open), 524while /HEADER should do for PERL.EXE (perl.exe is not a shared image). 525 526If your code 'use's modules, check to see if there is a shareable image for 527them, too. In the base perl build, POSIX, IO, Fcntl, Opcode, SDBM_File, 528DCLsym, and Stdio, and other extensions all have shared images that can be 529installed /SHARE. 530 531How much of a win depends on your memory situation, but if you are firing 532off perl with any regularity (like more than once every 20 seconds or so) 533it is probably beneficial to INSTALL at least portions of perl. 534 535While there is code in perl to remove privileges as it runs you are advised 536to NOT INSTALL PERL.EXE with PRIVs! 537 538=head2 Running h2ph to create perl header files (optional) on VMS 539 540If using HP C, ensure that you have extracted loose versions of your 541compiler's header or *.H files. Be sure to check the contents of: 542 543 SYS$LIBRARY:DECC$RTLDEF.TLB 544 SYS$LIBRARY:SYS$LIB_C.TLB 545 SYS$LIBRARY:SYS$STARLET_C.TLB 546 547etcetera. 548 549If using GNU cc then also check your GNU_CC:[000000...] tree for the locations 550of the GNU cc headers. 551 552=head1 Reporting Bugs 553 554If you come across what you think might be a bug in Perl, please report 555it. There's a script in PERL_ROOT:[UTILS], perlbug, that walks you through 556the process of creating a bug report. This script includes details of your 557installation, and is very handy. Completed bug reports should go to 558perlbug@perl.com. 559 560=head1 CAVEATS 561 562Probably the single biggest gotcha in compiling Perl is giving the wrong 563switches to MMS/MMK when you build. Use *exactly* what the configure.com 564script prints! 565 566The next big gotcha is directory depth. Perl can create directories four, 567five, or even six levels deep during the build, so you don't have to be 568too deep to start to hit the RMS 8 level limit (for ODS 2 volumes which were 569common on versions of VMS prior to V7.2 and even with V7.3 on the VAX). 570It is best to do: 571 572 DEFINE/TRANS=(CONC,TERM) PERLSRC "disk:[dir.dir.dir.perldir.]" 573 SET DEFAULT PERLSRC:[000000] 574 575before building in cases where you have to unpack the distribution so deep 576(note the trailing period in the definition of PERLSRC). Perl modules 577from CPAN can be just as bad (or worse), so watch out for them, too. Perl's 578configuration script will warn if it thinks you are too deep (at least on 579a VAX or on Alpha versions of VMS prior to 7.2). But MakeMaker will not 580warn you if you start out building a module too deep in a directory. 581 582As noted above ODS-5 escape sequences such as ^. can break the perl 583build. Solutions include renaming files and directories as needed or 584being careful to use the -o switch or /ODS2 qualifier with latter 585versions of the vmstar utility when unpacking perl or CPAN modules 586on ODS-5 volumes. 587 588Be sure that the process that you use to build perl has a PGFLQ greater 589than 100000. Be sure to have a correct local time zone to UTC offset 590defined (in seconds) in the logical name SYS$TIMEZONE_DIFFERENTIAL before 591running the regression test suite. The SYS$MANAGER:UTC$CONFIGURE_TDF.COM 592procedure will help you set that logical for your system but may require 593system privileges. For example, a location 5 hours west of UTC (such as 594the US East coast while not on daylight savings time) would have: 595 596 DEFINE SYS$TIMEZONE_DIFFERENTIAL "-18000" 597 598A final thing that causes trouble is leftover pieces from a failed 599build. If things go wrong make sure you do a "(MMK|MMS|make) realclean" 600before you rebuild. 601 602=head2 DEC C issues with Perl on VMS 603 604Note to DEC C users: Some early versions (pre-5.2, some pre-4. If you're DEC 605C 5.x or higher, with current patches if any, you're fine) of the DECCRTL 606contained a few bugs which affect Perl performance: 607 608=over 4 609 610=item - pipes 611 612Newlines are lost on I/O through pipes, causing lines to run together. 613This shows up as RMS RTB errors when reading from a pipe. You can 614work around this by having one process write data to a file, and 615then having the other read the file, instead of the pipe. This is 616fixed in version 4 of DEC C. 617 618=item - modf() 619 620The modf() routine returns a non-integral value for some values above 621INT_MAX; the Perl "int" operator will return a non-integral value in 622these cases. This is fixed in version 4 of DEC C. 623 624=item - ALPACRT ECO 625 626On the AXP, if SYSNAM privilege is enabled, the CRTL chdir() routine 627changes the process default device and directory permanently, even 628though the call specified that the change should not persist after 629Perl exited. This is fixed by DEC CSC patch ALPACRT04_061 or later. 630See also: 631 632 http://ftp.support.compaq.com/patches/.new/openvms.shtml 633 634=back 635 636Please note that in later versions "DEC C" may also be known as 637"Compaq C". 638 639=head2 GNU issues with Perl on VMS 640 641It has been a while since the GNU utilities such as GCC or GNU make 642were used to build perl on VMS. Hence they may require a great deal 643of source code modification to work again. 644 645 http://slacvx.slac.stanford.edu/HELP/GCC 646 http://www.progis.de/ 647 http://www.lp.se/products/gnu.html 648 649=head2 Floating Point Considerations 650 651Prior to 5.8.0, Perl simply accepted the default floating point options of the 652C compiler, namely representing doubles with D_FLOAT on VAX and G_FLOAT on 653Alpha. Single precision floating point values are represented in F_FLOAT 654format when either D_FLOAT or G_FLOAT is in use for doubles. Beginning with 6555.8.0, Alpha builds now use IEEE floating point formats by default, which in 656VMS parlance are S_FLOAT for singles and T_FLOAT for doubles. IEEE is not 657available on VAX, so F_FLOAT and D_FLOAT remain the defaults for singles and 658doubles respectively. The available non-default options are G_FLOAT on VAX 659and D_FLOAT or G_FLOAT on Alpha. 660 661The use of IEEE on Alpha introduces NaN, infinity, and denormalization 662capabilities not available with D_FLOAT and G_FLOAT. When using one of those 663non-IEEE formats, silent underflow and overflow are emulated in the conversion 664of strings to numbers, but it is preferable to get the real thing by using 665IEEE where possible. 666 667Regardless of what floating point format you consider preferable, be aware 668that the choice may have an impact on compatibility with external libraries, 669such as database interfaces, and with existing data, such as data created with 670the C<pack> function and written to disk, or data stored via the Storable 671extension. For example, a C<pack("d", $foo)")> will create a D_FLOAT, 672G_FLOAT, or T_FLOAT depending on what your Perl was configured with. When 673written to disk, the value can only be retrieved later by a Perl configured 674with the same floating point option that was in effect when it was created. 675 676To obtain a non-IEEE build on Alpha, simply answer no to the "Use IEEE math?" 677question during the configuration. To obtain an option different from the C 678compiler default on either VAX or Alpha, put in the option that you want in 679answer to the "Any additional cc flags?" question. For example, to obtain a 680G_FLOAT build on VAX, put in C</FLOAT=G_FLOAT>. 681 682=head2 Multinet issues with Perl on VMS 683 684Prior to the release of Perl 5.8.0 it was noted that the regression 685test for lib/Net/hostent (in file [.lib.Net]hostent.t) will fail owing 686to problems with the hostent structure returned by C calls to either 687gethostbyname() or gethostbyaddr() using DEC or Compaq C with a 688Multinet TCP/IP stack. The problem was noted in Multinet 4.3A 689using either Compaq C 6.5 or DEC C 6.0, and with Multinet 4.2A 690using DEC C 5.2, but could easily affect other versions of Multinet. 691Process Software Inc. has acknowledged a bug in the Multinet version 692of UCX$IPC_SHR and has provided an ECO for it. The ECO is called 693UCX_LIBRARY_EMULATION-010_A044 and is available from: 694 695 http://www.multinet.process.com/eco.html 696 697As of this writing, the ECO is only available for Multinet versions 6984.3A and later. You may determine the version of Multinet that you 699are running using the command: 700 701 multinet show /version 702 703from the DCL command prompt. 704 705If the ECO is unavailable for your version of Multinet and you are 706unable to upgrade, you might try using Perl programming constructs 707such as: 708 709 $address = substr($gethostbyname_addr,0,4); 710 711to temporarily work around the problem, or if you are brave 712and do not mind the possibility of breaking IPv6 addresses, 713you might modify the pp_sys.c file to add an ad-hoc correction 714like so: 715 716 717 --- pp_sys.c;1 Thu May 30 14:42:17 2002 718 +++ pp_sys.c Thu May 30 12:54:02 2002 719 @@ -4684,6 +4684,10 @@ 720 } 721 #endif 722 723 + if (hent) { 724 + hent->h_length = 4; 725 + } 726 + 727 if (GIMME != G_ARRAY) { 728 PUSHs(sv = sv_newmortal()); 729 if (hent) { 730 731then re-compile and re-test your perl. After the installation 732of the Multinet ECO you ought to back out any such changes though. 733 734=head1 Mailing Lists 735 736There are several mailing lists available to the Perl porter. For VMS 737specific issues (including both Perl questions and installation problems) 738there is the VMSPERL mailing list. It is usually a low-volume (10-12 739messages a week) mailing list. 740 741To subscribe, send a mail message to VMSPERL-SUBSCRIBE@PERL.ORG. The VMSPERL 742mailing list address is VMSPERL@PERL.ORG. Any mail sent there gets echoed 743to all subscribers of the list. There is a searchable archive of the list 744on the web at: 745 746 http://www.xray.mpe.mpg.de/mailing-lists/vmsperl/ 747 748To unsubscribe from VMSPERL send a message to VMSPERL-UNSUBSCRIBE@PERL.ORG. 749Be sure to do so from the subscribed account that you are canceling. 750 751=head2 Web sites for Perl on VMS 752 753Vmsperl pages on the web include: 754 755 http://www.sidhe.org/vmsperl/index.html 756 http://www.cpan.org/modules/by-module/VMS/ 757 http://www.xray.mpe.mpg.de/mailing-lists/vmsperl/ 758 http://www-ang.kfunigraz.ac.at/~binder/perl.html 759 http://lists.perl.org/showlist.cgi?name=vmsperl 760 http://archive.develooper.com/vmsperl@perl.org/ 761 http://h71000.www7.hp.com/openvms/products/ips/apache/csws_modperl.html 762 763=head1 SEE ALSO 764 765Perl information for users and programmers about the port of perl to VMS is 766available from the [.POD]PERLVMS.POD file that gets installed as L<perlvms>. 767For administrators the perlvms document also includes a detailed discussion 768of extending vmsperl with CPAN modules after Perl has been installed. 769 770=head1 AUTHORS 771 772Originally by Charles Bailey bailey@newman.upenn.edu. See the git repository 773for history. 774 775=head1 ACKNOWLEDGEMENTS 776 777A real big thanks needs to go to Charles Bailey 778bailey@newman.upenn.edu, who is ultimately responsible for Perl 5.004 779running on VMS. Without him, nothing the rest of us have done would be at 780all important. 781 782There are, of course, far too many people involved in the porting and testing 783of Perl to mention everyone who deserves it, so please forgive us if we've 784missed someone. That said, special thanks are due to the following: 785 786 Tim Adye T.J.Adye@rl.ac.uk 787 for the VMS emulations of getpw*() 788 David Denholm denholm@conmat.phys.soton.ac.uk 789 for extensive testing and provision of pipe and SocketShr code, 790 Mark Pizzolato mark@infocomm.com 791 for the getredirection() code 792 Rich Salz rsalz@bbn.com 793 for readdir() and related routines 794 Peter Prymmer pvhp@best.com 795 for extensive testing, as well as development work on 796 configuration and documentation for VMS Perl, 797 Dan Sugalski dan@sidhe.org 798 for extensive contributions to recent version support, 799 development of VMS-specific extensions, and dissemination 800 of information about VMS Perl, 801 the Stanford Synchrotron Radiation Laboratory and the 802 Laboratory of Nuclear Studies at Cornell University for 803 the opportunity to test and develop for the AXP, 804 John Hasstedt John.Hasstedt@sunysb.edu 805 for VAX VMS V7.2 support 806 John Malmberg wb8tyw@qsl.net 807 for ODS-5 filename handling and other modernizations 808 809and to the entire VMSperl group for useful advice and suggestions. In 810addition the perl5-porters deserve credit for their creativity and 811willingness to work with the VMS newcomers. Finally, the greatest debt of 812gratitude is due to Larry Wall larry@wall.org, for having the ideas which 813have made our sleepless nights possible. 814 815Thanks, 816The VMSperl group 817 818=cut 819 820

