{
    "mode": "man",
    "parameter": "perlvms",
    "section": "1",
    "url": "https://www.chedong.com/phpMan.php/man/perlvms/1/json",
    "generated": "2026-10-09T08:27:36Z",
    "sections": {
        "NAME": {
            "content": "perlvms - VMS-specific documentation for Perl\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "Gathered below are notes describing details of Perl 5's behavior on VMS.  They are a\nsupplement to the regular Perl 5 documentation, so we have focussed on the ways in which Perl\n5 functions differently under VMS than it does under Unix, and on the interactions between\nPerl and the rest of the operating system.  We haven't tried to duplicate complete\ndescriptions of Perl features from the main Perl documentation, which can be found in the\n[.pod] subdirectory of the Perl distribution.\n\nWe hope these notes will save you from confusion and lost sleep when writing Perl scripts on\nVMS.  If you find we've missed something you think should appear here, please don't hesitate\nto drop a line to vmsperl@perl.org.\n",
            "subsections": []
        },
        "Installation": {
            "content": "Directions for building and installing Perl 5 can be found in the file README.vms in the main\nsource directory of the Perl distribution.\n",
            "subsections": []
        },
        "Organization of Perl Images": {
            "content": "",
            "subsections": [
                {
                    "name": "Core Images",
                    "content": "During the build process, three Perl images are produced.  Miniperl.Exe is an executable\nimage which contains all of the basic functionality of Perl, but cannot take advantage of\nPerl XS extensions and has a hard-wired list of library locations for loading pure-Perl\nmodules.  It is used extensively to build and test Perl and various extensions, but is not\ninstalled.\n\nMost of the complete Perl resides in the shareable image PerlShr.Exe, which provides a core\nto which the Perl executable image and all Perl extensions are linked. It is generally\nlocated via the logical name PERLSHR.  While it's possible to put the image in SYS$SHARE to\nmake it loadable, that's not recommended. And while you may wish to INSTALL the image for\nperformance reasons, you should not install it with privileges; if you do, the result will\nnot be what you expect as image privileges are disabled during Perl start-up.\n\nFinally, Perl.Exe is an executable image containing the main entry point for Perl, as well as\nsome initialization code.  It should be placed in a public directory, and made world\nexecutable.  In order to run Perl with command line arguments, you should define a foreign\ncommand to invoke this image.\n"
                },
                {
                    "name": "Perl Extensions",
                    "content": "Perl extensions are packages which provide both XS and Perl code to add new functionality to\nperl.  (XS is a meta-language which simplifies writing C code which interacts with Perl, see\nperlxs for more details.)  The Perl code for an extension is treated like any other library\nmodule - it's made available in your script through the appropriate \"use\" or \"require\"\nstatement, and usually defines a Perl package containing the extension.\n\nThe portion of the extension provided by the XS code may be connected to the rest of Perl in\neither of two ways.  In the static configuration, the object code for the extension is linked\ndirectly into PerlShr.Exe, and is initialized whenever Perl is invoked.  In the dynamic\nconfiguration, the extension's machine code is placed into a separate shareable image, which\nis mapped by Perl's DynaLoader when the extension is \"use\"d or \"require\"d in your script.\nThis allows you to maintain the extension as a separate entity, at the cost of keeping track\nof the additional shareable image.  Most extensions can be set up as either static or\ndynamic.\n\nThe source code for an extension usually resides in its own directory.  At least three files\nare generally provided: Extshortname.xs (where Extshortname is the portion of the extension's\nname following the last \"::\"), containing the XS code, Extshortname.pm, the Perl library\nmodule for the extension, and Makefile.PL, a Perl script which uses the \"MakeMaker\" library\nmodules supplied with Perl to generate a Descrip.MMS file for the extension.\n"
                },
                {
                    "name": "Installing static extensions",
                    "content": "Since static extensions are incorporated directly into PerlShr.Exe, you'll have to rebuild\nPerl to incorporate a new extension.  You should edit the main Descrip.MMS or Makefile you\nuse to build Perl, adding the extension's name to the \"ext\" macro, and the extension's object\nfile to the \"extobj\" macro.  You'll also need to build the extension's object file, either by\nadding dependencies to the main Descrip.MMS, or using a separate Descrip.MMS for the\nextension.  Then, rebuild PerlShr.Exe to incorporate the new code.\n\nFinally, you'll need to copy the extension's Perl library module to the [.Extname]\nsubdirectory under one of the directories in @INC, where Extname is the name of the\nextension, with all \"::\" replaced by \".\" (e.g.  the library module for extension Foo::Bar\nwould be copied to a [.Foo.Bar] subdirectory).\n"
                },
                {
                    "name": "Installing dynamic extensions",
                    "content": "In general, the distributed kit for a Perl extension includes a file named Makefile.PL, which\nis a Perl program which is used to create a Descrip.MMS file which can be used to build and\ninstall the files required by the extension.  The kit should be unpacked into a directory\ntree not under the main Perl source directory, and the procedure for building the extension\nis simply\n\n$ perl Makefile.PL  ! Create Descrip.MMS\n$ mmk               ! Build necessary files\n$ mmk test          ! Run test code, if supplied\n$ mmk install       ! Install into public Perl tree\n\nVMS support for this process in the current release of Perl is sufficient to handle most\nextensions.  (See the MakeMaker documentation for more details on installation options for\nextensions.)\n\n•   the  [.Lib.Auto.Arch$PVersExtname]  subdirectory of one of the directories in @INC (where\nPVers is the version of Perl you're using, as supplied in $], with '.' converted to ''),\nor\n\n•   one of the directories in @INC, or\n\n•   a directory which the extensions Perl library module passes to the DynaLoader when asking\nit to map the shareable image, or\n\n•   Sys$Share or Sys$Library.\n\nIf the shareable image isn't in any of these places, you'll need to  define  a  logical  name\nExtshortname,  where Extshortname is the portion of the extension's name after the last \"::\",\nwhich translates to the full file specification of the shareable image.\n"
                }
            ]
        },
        "File specifications": {
            "content": "",
            "subsections": [
                {
                    "name": "Syntax",
                    "content": "We have tried to make Perl  aware  of  both  VMS-style  and  Unix-style  file  specifications\nwherever  possible.   You  may use either style, or both, on the command line and in scripts,\nbut you may not combine the  two  styles  within  a  single  file  specification.   VMS  Perl\ninterprets  Unix  pathnames  in much the same way as the CRTL (e.g. the first component of an\nabsolute path is read as the device name for the VMS file specification).  There are a set of\nfunctions provided in the \"VMS::Filespec\" package for explicit  interconversion  between  VMS\nand Unix syntax; its documentation provides more details.\n\nWe've  tried  to  minimize the dependence of Perl library modules on Unix syntax, but you may\nfind that some of these, as well as some scripts written for Unix systems, will require  that\nyou use Unix syntax, since they will assume that '/' is the directory separator, etc.  If you\nfind  instances of this in the Perl distribution itself, please let us know, so we can try to\nwork around them.\n\nAlso when working on Perl programs on VMS, if you need  a  syntax  in  a  specific  operating\nsystem format, then you need either to check the appropriate DECC$ feature logical, or call a\nconversion routine to force it to that format.\n\nThe  feature logical name DECC$FILENAMEUNIXREPORT modifies traditional Perl behavior in the\nconversion of file specifications from Unix to VMS format in order  to  follow  the  extended\ncharacter  handling  rules  now  expected by the CRTL.  Specifically, when this feature is in\neffect, the \"./.../\" in a  Unix  path  is  now  translated  to  \"[.^.^.^.]\"  instead  of  the\ntraditional  VMS \"[...]\".  To be compatible with what MakeMaker expects, if a VMS path cannot\nbe translated to a Unix path, it is passed through unchanged, so unixify(\"[...]\") will return\n\"[...]\".\n\nThere are several ambiguous cases where a conversion  routine  cannot  determine  whether  an\ninput  filename  is  in  Unix  format  or  in  VMS  format,  since now both VMS and Unix file\nspecifications may have characters in them that could be mistaken for  syntax  delimiters  of\nthe  other type. So some pathnames simply cannot be used in a mode that allows either type of\npathname to be present.  Perl will tend to assume that  an  ambiguous  filename  is  in  Unix\nformat.\n\nAllowing  \".\"  as  a  version  delimiter  is  simply  incompatible with determining whether a\npathname is in VMS format or in Unix format with extended file syntax.  There is  no  way  to\nknow  whether  \"perl-5.8.6\"  is  a Unix \"perl-5.8.6\" or a VMS \"perl-5.8;6\" when passing it to\nunixify() or vmsify().\n\nThe DECC$FILENAMEUNIXREPORT logical name controls how  Perl  interprets  filenames  to  the\nextent  that  Perl  uses  the  CRTL internally for many purposes, and attempts to follow CRTL\nconventions for reporting filenames.  The DECC$FILENAMEUNIXONLY feature differs in that  it\nexpects all filenames passed to the C run-time to be already in Unix format.  This feature is\nnot  yet supported in Perl since Perl uses traditional OpenVMS file specifications internally\nand in the test harness, and it is not yet clear whether this mode will be useful or useable.\nThe feature logical name DECC$POSIXCOMPLIANTPATHNAMES is new with the RMS Symbolic Link SDK\nand included with OpenVMS v8.3, but is not yet supported in Perl.\n"
                },
                {
                    "name": "Filename Case",
                    "content": "Perl enables DECC$EFSCASEPRESERVE and DECC$ARGVPARSESTYLE  by  default.   Note  that  the\nlatter  only takes effect when extended parse is set in the process in which Perl is running.\nWhen these features are explicitly disabled in the environment or the CRTL does  not  support\nthem,  Perl  follows  the  traditional CRTL behavior of downcasing command-line arguments and\nreturning file specifications in lower case only.\n\nN. B.  It is very easy to get  tripped  up  using  a  mixture  of  other  programs,  external\nutilities,  and  Perl  scripts  that  are  in  varying  states  of  being able to handle case\npreservation.  For example, a file created by an older version of an  archive  utility  or  a\nbuild  utility  such as MMK or MMS may generate a filename in all upper case even on an ODS-5\nvolume.  If this filename is later retrieved by a Perl script or module in a case  preserving\nenvironment,  that upper case name may not match the mixed-case or lower-case expectations of\nthe Perl code.  Your best bet is to follow an all-or-nothing approach to  case  preservation:\neither  don't  use  it at all, or make sure your entire toolchain and application environment\nsupport and use it.\n\nOpenVMS Alpha v7.3-1 and later and all version of OpenVMS I64 support case sensitivity  as  a\nprocess  setting  (see \"SET PROCESS /CASELOOKUP=SENSITIVE\"). Perl does not currently support\ncase sensitivity on VMS, but  it  may  in  the  future,  so  Perl  programs  should  use  the\n\"File::Spec->casetolerant\" method to determine the state, and not the $^O variable.\n"
                },
                {
                    "name": "Symbolic Links",
                    "content": "When  built on an ODS-5 volume with symbolic links enabled, Perl by default supports symbolic\nlinks when the requisite support is available in the filesystem and  CRTL  (generally  64-bit\nOpenVMS  v8.3  and later).  There are a number of limitations and caveats to be aware of when\nworking with symbolic links on VMS.  Most notably, the target of a valid symbolic  link  must\nbe  expressed as a Unix-style path and it must exist on a volume visible from your POSIX root\n(see the \"SHOW ROOT\" command in DCL help).  For further details on symbolic link capabilities\nand requirements, see chapter 12 of the CRTL manual that ships with OpenVMS v8.3 or later.\n"
                },
                {
                    "name": "Wildcard expansion",
                    "content": "File specifications containing wildcards are allowed both on the command line and within Perl\nglobs (e.g. \"<*.c>\").  If the wildcard filespec uses VMS syntax, the resultant filespecs will\nfollow VMS syntax; if a Unix-style filespec  is  passed  in,  Unix-style  filespecs  will  be\nreturned.   Similar  to  the  behavior  of wildcard globbing for a Unix shell, one can escape\ncommand line wildcards with double quotation marks \"\"\" around a  perl  program  command  line\nargument.  However, owing to the stripping of \"\"\" characters carried out by the C handling of\nargv  you  will  need  to  escape a construct such as this one (in a directory containing the\nfiles PERL.C, PERL.EXE, PERL.H, and PERL.OBJ):\n\n$ perl -e \"print join(' ',@ARGV)\" perl.*\nperl.c perl.exe perl.h perl.obj\n\nin the following triple quoted manner:\n\n$ perl -e \"print join(' ',@ARGV)\" \"\"\"perl.*\"\"\"\nperl.*\n\nIn both the case of unquoted command line arguments  or  in  calls  to  glob()  VMS  wildcard\nexpansion   is   performed.   (csh-style   wildcard   expansion   is  available  if  you  use\n\"File::Glob::glob\".)  If the wildcard filespec contains a device or directory  specification,\nthen  the resultant filespecs will also contain a device and directory; otherwise, device and\ndirectory information are removed.  VMS-style resultant filespecs will contain a full  device\nand  directory, while Unix-style resultant filespecs will contain only as much of a directory\npath as was present in the input  filespec.   For  example,  if  your  default  directory  is\nPerlRoot:[000000],    the    expansion    of    \"[.t]*.*\"   will   yield   filespecs    like\n\"perlroot:[t]base.dir\",  while  the  expansion  of  \"t/*/*\"  will   yield   filespecs   like\n\"t/base.dir\".   (This  is  done  to  match  the  behavior of glob expansion performed by Unix\nshells.)\n\nSimilarly, the resultant filespec will contain the file version only if one  was  present  in\nthe input filespec.\n"
                },
                {
                    "name": "Pipes",
                    "content": "Input  and  output  pipes  to  Perl  filehandles  are supported; the \"file name\" is passed to\nlib$spawn() for asynchronous execution.  You should be careful to close any  pipes  you  have\nopened in a Perl script, lest you leave any \"orphaned\" subprocesses around when Perl exits.\n\nYou  may  also  use  backticks to invoke a DCL subprocess, whose output is used as the return\nvalue of the expression.  The string between the backticks is  handled  as  if  it  were  the\nargument  to  the  \"system\"  operator  (see  below).   In  this  case, Perl will wait for the\nsubprocess to complete before continuing.\n\nThe mailbox (MBX) that perl can create to communicate with a pipe defaults to a  buffer  size\nof 8192 on 64-bit systems, 512 on VAX.  The default buffer size is adjustable via the logical\nname  PERLMBXSIZE provided that the value falls between 128 and the SYSGEN parameter MAXBUF\ninclusive.  For example, to set the  mailbox  size  to  32767  use  \"$ENV{'PERLMBXSIZE'}  =\n32767;\" and then open and use pipe constructs.  An alternative would be to issue the command:\n\n$ Define PERLMBXSIZE 32767\n\nbefore  running your wide record pipe program.  A larger value may improve performance at the\nexpense of the BYTLM UAF quota.\n\nPERL5LIB and PERLLIB\nThe PERL5LIB and PERLLIB environment elements work as documented in  perl,  except  that  the\nelement  separator  is,  by  default, '|' instead of ':'.  However, when running under a Unix\nshell as determined by the logical name \"GNV$UNIXSHELL\", the separator will  be  ':'  as  on\nUnix systems. The directory specifications may use either VMS or Unix syntax.\n"
                }
            ]
        },
        "The Perl Forked Debugger": {
            "content": "The  Perl forked debugger places the debugger commands and output in a separate X-11 terminal\nwindow so that commands and output from multiple processes are not mixed together.\n\nPerl on VMS supports an emulation of the forked debugger when Perl is run  on  a  VMS  system\nthat has X11 support installed.\n\nTo  use  the  forked debugger, you need to have the default display set to an X-11 Server and\nsome environment variables set that Unix expects.\n\nThe forked debugger  requires  the  environment  variable  \"TERM\"  to  be  \"xterm\",  and  the\nenvironment variable \"DISPLAY\" to exist.  \"xterm\" must be in lower case.\n\n$define TERM \"xterm\"\n\n$define DISPLAY \"hostname:0.0\"\n\nCurrently  the  value  of  \"DISPLAY\"  is ignored.  It is recommended that it be set to be the\nhostname of the display, the server and screen in Unix notation.  In the future the value  of\nDISPLAY may be honored by Perl instead of using the default display.\n\nIt  may  be  helpful  to  always use the forked debugger so that script I/O is separated from\ndebugger I/O.  You can force the debugger to be forked by assigning a value  to  the  logical\nname <PERLDBPIDS> that is not a process identification number.\n\n$define PERLDBPIDS XXXX\n",
            "subsections": []
        },
        "PERLVMSEXCEPTIONDEBUG": {
            "content": "The  PERLVMSEXCEPTIONDEBUG  being  defined  as  \"ENABLE\" will cause the VMS debugger to be\ninvoked if a fatal exception that is not otherwise handled is raised.  The purpose of this is\nto allow debugging of internal Perl problems that would cause such a condition.\n\nThis allows the programmer to look at the execution stack and variables to find out the cause\nof the exception.  As the debugger is being invoked as the Perl interpreter is about to do  a\nfatal exit, continuing the execution in debug mode is usually not practical.\n\nStarting Perl in the VMS debugger may change the program execution profile in a way that such\nproblems are not reproduced.\n\nThe \"kill\" function can be used to test this functionality from within a program.\n\nIn  typical  VMS  style,  only the first letter of the value of this logical name is actually\nchecked in a case insensitive mode, and it is considered enabled if it is the  value  \"T\",\"1\"\nor \"E\".\n\nThis logical name must be defined before Perl is started.\n",
            "subsections": []
        },
        "Command line": {
            "content": "",
            "subsections": [
                {
                    "name": "I/O redirection and backgrounding",
                    "content": "Perl  for VMS supports redirection of input and output on the command line, using a subset of\nBourne shell syntax:\n\n•   \"<file\" reads stdin from \"file\",\n\n•   \">file\" writes stdout to \"file\",\n\n•   \">>file\" appends stdout to \"file\",\n\n•   \"2>file\" writes stderr to \"file\",\n\n•   \"2>>file\" appends stderr to \"file\", and\n\n•   \"2>&1\" redirects stderr to stdout.\n\nIn addition, output may be piped to a subprocess, using the character  '|'.   Anything  after\nthis  character  on  the command line is passed to a subprocess for execution; the subprocess\ntakes the output of Perl as its input.\n\nFinally, if the command line ends with '&', the entire command is run in the background as an\nasynchronous subprocess.\n"
                },
                {
                    "name": "Command line switches",
                    "content": "The following command line switches behave differently under VMS than described  in  perlrun.\nNote  also  that  in  order  to  pass uppercase switches to Perl, you need to enclose them in\ndouble-quotes on the command line, since the CRTL downcases all unquoted strings.\n\nOn newer 64 bit versions of OpenVMS, a process setting now controls if the quoting is  needed\nto preserve the case of command line arguments.\n\n-i  If  the  \"-i\" switch is present but no extension for a backup copy is given, then inplace\nediting creates a new version of a file; the existing copy is not deleted.  (Note that if\nan extension is given, an existing file is renamed to the backup file,  as  is  the  case\nunder  other  operating  systems,  so  it does not remain as a previous version under the\noriginal filename.)\n\n-S  If the \"-S\" or \"-\"S\"\" switch is present and the script name does not contain a directory,\nthen Perl translates the logical name DCL$PATH as a searchlist, using each translation as\na directory in which to look for the script.  In addition, if no file type is  specified,\nPerl looks in each directory for a file matching the name specified, with a blank type, a\ntype of .pl, and a type of .com, in that order.\n\n-u  The \"-u\" switch causes the VMS debugger to be invoked after the Perl program is compiled,\nbut before it has run.  It does not create a core dump file.\n"
                }
            ]
        },
        "Perl functions": {
            "content": "As  of the time this document was last revised, the following Perl functions were implemented\nin the VMS port of Perl (functions marked with * are discussed in more detail below):\n\nfile tests*, abs, alarm, atan, backticks*, binmode*, bless,\ncaller, chdir, chmod, chown, chomp, chop, chr,\nclose, closedir, cos, crypt*, defined, delete, die, do, dump*,\neach, endgrent, endpwent, eof, eval, exec*, exists, exit, exp,\nfileno, flock  getc, getgrent*, getgrgid*, getgrnam, getlogin,\ngetppid, getpwent*, getpwnam*, getpwuid*, glob, gmtime*, goto,\ngrep, hex, ioctl, import, index, int, join, keys, kill*,\nlast, lc, lcfirst, lchown*, length, link*, local, localtime, log,\nlstat, m//, map, mkdir, my, next, no, oct, open, opendir, ord,\npack, pipe, pop, pos, print, printf, push, q//, qq//, qw//,\nqx//*, quotemeta, rand, read, readdir, readlink*, redo, ref,\nrename, require, reset, return, reverse, rewinddir, rindex,\nrmdir, s///, scalar, seek, seekdir, select(internal),\nselect (system call)*, setgrent, setpwent, shift, sin, sleep,\nsocketpair, sort, splice, split, sprintf, sqrt, srand, stat,\nstudy, substr, symlink*, sysread, system*, syswrite, tell,\ntelldir, tie, time, times*, tr///, uc, ucfirst, umask,\nundef, unlink*, unpack, untie, unshift, use, utime*,\nvalues, vec, wait, waitpid*, wantarray, warn, write, y///\n\nThe following functions were not implemented in the VMS port, and  calling  them  produces  a\nfatal error (usually) or undefined behavior (rarely, we hope):\n\nchroot, dbmclose, dbmopen, fork*, getpgrp, getpriority,\nmsgctl, msgget, msgsend, msgrcv, semctl,\nsemget, semop, setpgrp, setpriority, shmctl, shmget,\nshmread, shmwrite, syscall\n\nThe following functions are available on Perls compiled with Dec C 5.2 or greater and running\nVMS 7.0 or greater:\n\ntruncate\n\nThe following functions are available on Perls built on VMS 7.2 or greater:\n\nfcntl (without locking)\n\nThe  following  functions  may  or  may  not be implemented, depending on what type of socket\nsupport you've built into your copy of Perl:\n\naccept, bind, connect, getpeername,\ngethostbyname, getnetbyname, getprotobyname,\ngetservbyname, gethostbyaddr, getnetbyaddr,\ngetprotobynumber, getservbyport, gethostent,\ngetnetent, getprotoent, getservent, sethostent,\nsetnetent, setprotoent, setservent, endhostent,\nendnetent, endprotoent, endservent, getsockname,\ngetsockopt, listen, recv, select(system call)*,\nsend, setsockopt, shutdown, socket\n\nThe following function is available on Perls built on 64 bit OpenVMS  v8.2  with  hard  links\nenabled  on  an  ODS-5  formatted  build  disk.  CRTL support is in principle available as of\nOpenVMS v7.3-1, and better configuration support could detect this.\n\nlink\n\nThe following functions are available on Perls built on 64 bit OpenVMS v8.2 and later.   CRTL\nsupport  is  in  principle  available  as of OpenVMS v7.3-2, and better configuration support\ncould detect this.\n\ngetgrgid, getgrnam, getpwnam, getpwuid,\nsetgrent, ttyname\n\nThe following functions are available on Perls built on 64 bit OpenVMS v8.2 and later.\n\nstatvfs, socketpair\n\nFile tests\nThe tests \"-b\", \"-B\", \"-c\", \"-C\", \"-d\", \"-e\", \"-f\", \"-o\", \"-M\", \"-s\", \"-S\",  \"-t\",  \"-T\",\nand \"-z\" work as advertised.  The return values for \"-r\", \"-w\", and \"-x\" tell you whether\nyou  can  actually  access the file; this may not reflect the UIC-based file protections.\nSince real and effective UIC don't differ under VMS,  \"-O\",  \"-R\",  \"-W\",  and  \"-X\"  are\nequivalent  to  \"-o\",  \"-r\",  \"-w\",  and \"-x\".  Similarly, several other tests, including\n\"-A\", \"-g\", \"-k\", \"-l\", \"-p\", and \"-u\", aren't particularly meaningful under VMS, and the\nvalues returned by these tests reflect whatever your CRTL  stat()  routine  does  to  the\nequivalent  bits  in  the  stmode  field.  Finally, \"-d\" returns true if passed a device\nspecification without an explicit directory (e.g.  \"DUA1:\"),  as  well  as  if  passed  a\ndirectory.\n\nThere  are  DECC feature logical names AND ODS-5 volume attributes that also control what\nvalues are returned for the date fields.\n\nNote: Some sites have reported problems when using the file-access tests (\"-r\", \"-w\", and\n\"-x\") on files accessed via DEC's  DFS.   Specifically,  since  DFS  does  not  currently\nprovide  access  to  the  extended  file  header  of files on remote volumes, attempts to\nexamine the ACL fail, and the file tests will return false, with $! indicating  that  the\nfile  does  not  exist.   You  can use \"stat\" on these files, since that checks UIC-based\nprotection only, and then manually check the appropriate  bits,  as  defined  by  your  C\ncompiler's  stat.h,  in  the  mode  value it returns, if you need an approximation of the\nfile's protections.\n\nbackticks\nBackticks create a subprocess, and pass the enclosed string to it for execution as a  DCL\ncommand.   Since  the  subprocess  is  created  directly via \"lib$spawn()\", any valid DCL\ncommand string may be specified.\n\nbinmode FILEHANDLE\nThe \"binmode\" operator will attempt to insure that no  translation  of  carriage  control\noccurs  on  input  from  or output to this filehandle.  Since this involves reopening the\nfile and then restoring its file position indicator, if this function returns FALSE,  the\nunderlying  filehandle  may  no longer point to an open file, or may point to a different\nposition in the file than before \"binmode\" was called.\n\nNote that \"binmode\" is generally not necessary  when  using  normal  filehandles;  it  is\nprovided  so that you can control I/O to existing record-structured files when necessary.\nYou can also use the \"vmsfopen\" function  in  the  VMS::Stdio  extension  to  gain  finer\ncontrol of I/O to files and devices with different record structures.\n\ncrypt PLAINTEXT, USER\nThe  \"crypt\"  operator uses the \"sys$hashpassword\" system service to generate the hashed\nrepresentation of PLAINTEXT.  If USER is a valid username, the algorithm and salt  values\nare  taken from that user's UAF record.  If it is not, then the preferred algorithm and a\nsalt of 0 are used.  The quadword encrypted value is returned as an 8-character string.\n\nThe value returned by \"crypt\" may be compared against the encrypted password from the UAF\nreturned by the \"getpw*\" functions, in order to authenticate users.  If you're  going  to\ndo  this,  remember  that the encrypted password in the UAF was generated using uppercase\nusername and password strings; you'll have to upcase the arguments to \"crypt\"  to  insure\nthat you'll get the proper value:\n\nsub validatepasswd {\nmy($user,$passwd) = @;\nmy($pwdhash);\nif ( !($pwdhash = (getpwnam($user))[1]) ||\n$pwdhash ne crypt(\"\\U$passwd\",\"\\U$name\") ) {\nintruderalert($name);\n}\nreturn 1;\n}\n\ndie \"die\"  will force the native VMS exit status to be an SS$ABORT code if neither of the $!\nor $? status values are ones that would cause the native  status  to  be  interpreted  as\nbeing what VMS classifies as SEVEREERROR severity for DCL error handling.\n\nWhen  \"PERLVMSPOSIXEXIT\"  is active (see \"$?\" below), the native VMS exit status value\nwill have either one of the $! or $? or $^E or the Unix value 255 encoded into  it  in  a\nway  that  the  effective  original  value can be decoded by other programs written in C,\nincluding Perl and the GNV package.  As per the  normal  non-VMS  behavior  of  \"die\"  if\neither  $!  or  $?  are  non-zero,  one of those values will be encoded into a native VMS\nstatus value.  If both of the Unix status values are 0, and the $^E value is set  one  of\nERROR  or  SEVEREERROR severity, then the $^E value will be used as the exit code as is.\nIf none of the above apply, the Unix value of 255 will be encoded into a native VMS  exit\nstatus value.\n\nPlease   note   a   significant   difference   in   the   behavior   of   \"die\"   in  the\n\"PERLVMSPOSIXEXIT\" mode is that it does not force a VMS SEVEREERROR status  on  exit.\nThe  Unix exit values of 2 through 255 will be encoded in VMS status values with severity\nlevels of SUCCESS.  The Unix exit value of 1 will be encoded in a VMS status value with a\nseverity level of ERROR.  This is to be compatible with how the  VMS  C  library  encodes\nthese values.\n\nThe  minimum  severity level set by \"die\" in \"PERLVMSPOSIXEXIT\" mode may be changed to\nbe ERROR or higher in the future depending on the results of testing and further review.\n\nSee \"$?\" for a description of the encoding of the Unix value  to  produce  a  native  VMS\nstatus containing it.\n\ndump\nRather  than  causing  Perl  to  abort and dump core, the \"dump\" operator invokes the VMS\ndebugger.  If you continue to execute the Perl program under the debugger,  control  will\nbe  transferred  to  the  label  specified as the argument to \"dump\", or, if no label was\nspecified, back to the beginning of the program.  All other state of  the  program  (e.g.\nvalues of variables, open file handles) are not affected by calling \"dump\".\n\nexec LIST\nA  call to \"exec\" will cause Perl to exit, and to invoke the command given as an argument\nto \"exec\" via \"lib$docommand\".  If the argument begins with '@' or '$'  (other  than  as\npart of a filespec), then it is executed as a DCL command.  Otherwise, the first token on\nthe command line is treated as the filespec of an image to run, and an attempt is made to\ninvoke  it (using .Exe and the process defaults to expand the filespec) and pass the rest\nof \"exec\"'s argument to it as parameters.  If the token has no file type, and  matches  a\nfile  with  null  type,  then  an  attempt  is  made  to determine whether the file is an\nexecutable image which should be invoked using \"MCR\" or  a  text  file  which  should  be\npassed to DCL as a command procedure.\n\nfork\nWhile in principle the \"fork\" operator could be implemented via (and with the same rather\nsevere  limitations  as)  the CRTL vfork() routine, and while some internal support to do\njust that is in place,  the  implementation  has  never  been  completed,  making  \"fork\"\ncurrently  unavailable.  A true kernel fork() is expected in a future version of VMS, and\nthe pseudo-fork based on interpreter threads may be available in a future version of Perl\non VMS (see perlfork).  In the meantime, use \"system\", backticks, or piped filehandles to\ncreate subprocesses.\n\ngetpwent\ngetpwnam\ngetpwuid\nThese operators obtain the information described in perlfunc, if you have the  privileges\nnecessary  to  retrieve  the named user's UAF information via \"sys$getuai\".  If not, then\nonly the $name, $uid, and $gid items are returned.  The  $dir  item  contains  the  login\ndirectory  in  VMS  syntax,  while the $comment item contains the login directory in Unix\nsyntax. The $gcos item contains the owner field from the UAF record.  The $quota item  is\nnot used.\n\ngmtime\nThe \"gmtime\" operator will function properly if you have a working CRTL gmtime() routine,\nor  if  the  logical  name  SYS$TIMEZONEDIFFERENTIAL is defined as the number of seconds\nwhich must be added  to  UTC  to  yield  local  time.   (This  logical  name  is  defined\nautomatically if you are running a version of VMS with built-in UTC support.)  If neither\nof these cases is true, a warning message is printed, and \"undef\" is returned.\n\nkill\nIn  most  cases, \"kill\" is implemented via the undocumented system service $SIGPRC, which\nhas the same calling sequence as $FORCEX, but throws an exception in the  target  process\nrather than forcing it to call $EXIT.  Generally speaking, \"kill\" follows the behavior of\nthe  CRTL's  kill() function, but unlike that function can be called from within a signal\nhandler.  Also, unlike the \"kill\" in some versions of the CRTL, Perl's \"kill\" checks  the\nvalidity  of  the signal passed in and returns an error rather than attempting to send an\nunrecognized signal.\n\nAlso, negative signal values don't do anything special under VMS; they're just  converted\nto the corresponding positive value.\n\nqx//\nSee the entry on \"backticks\" above.\n\nselect (system call)\nIf  Perl  was  not  built with socket support, the system call version of \"select\" is not\navailable at all.  If socket support is present, then the system call version of \"select\"\nfunctions only for file descriptors attached to sockets.  It will not provide information\nabout regular files or pipes, since the CRTL  select()  routine  does  not  provide  this\nfunctionality.\n\nstat EXPR\nSince VMS keeps track of files according to a different scheme than Unix, it's not really\npossible  to  represent  the  file's  ID in the \"stdev\" and \"stino\" fields of a \"struct\nstat\".  Perl tries its best, though, and the values it uses are pretty unlikely to be the\nsame for two different files.  We can't guarantee this, though, so caveat scriptor.\n\nsystem LIST\nThe \"system\" operator creates a subprocess, and passes its arguments  to  the  subprocess\nfor  execution  as  a  DCL  command.   Since  the  subprocess  is  created  directly  via\n\"lib$spawn()\", any valid DCL command string may be specified.  If the string begins  with\n'@',  it  is  treated  as  a  DCL command unconditionally.  Otherwise, if the first token\ncontains a character used as a delimiter in file specification  (e.g.  \":\"  or  \"]\"),  an\nattempt  is made to expand it using  a default type of .Exe and the process defaults, and\nif successful, the resulting file is invoked via \"MCR\". This  allows  you  to  invoke  an\nimage  directly  simply  by  passing the file specification to \"system\", a common Unixish\nidiom.  If the token has no file type, and matches a file with null type, then an attempt\nis made to determine whether the file is an executable  image  which  should  be  invoked\nusing \"MCR\" or a text file which should be passed to DCL as a command procedure.\n\nIf  LIST  consists of the empty string, \"system\" spawns an interactive DCL subprocess, in\nthe same fashion as typing SPAWN at the DCL prompt.\n\nPerl waits for the subprocess to complete before  continuing  execution  in  the  current\nprocess.  As described in perlfunc, the return value of \"system\" is a fake \"status\" which\nfollows  POSIX  semantics  unless  the pragma \"use vmsish 'status'\" is in effect; see the\ndescription of $? in this document for more detail.\n\ntime\nThe value returned by \"time\" is the offset in seconds  from  01-JAN-1970  00:00:00  (just\nlike  the  CRTL's  times() routine), in order to make life easier for code coming in from\nthe POSIX/Unix world.\n\ntimes\nThe array returned by the \"times\" operator is divided up according to the same rules  the\nCRTL  times()  routine.   Therefore,  the  \"system time\" elements will always be 0, since\nthere is no difference between \"user time\" and \"system\" time  under  VMS,  and  the  time\naccumulated  by  a subprocess may or may not appear separately in the \"child time\" field,\ndepending on whether times() keeps track of  subprocesses  separately.   Note  especially\nthat  the  VAXCRTL  (at  least) keeps track only of subprocesses spawned using fork() and\nexec(); it will not accumulate the times of subprocesses spawned via pipes, system(),  or\nbackticks.\n\nunlink LIST\n\"unlink\" will delete the highest version of a file only; in order to delete all versions,\nyou need to say\n\n1 while unlink LIST;\n\nYou  may  need to make this change to scripts written for a Unix system which expect that\nafter a call to \"unlink\", no files with the names passed to \"unlink\" will exist.   (Note:\nThis    can    be    changed    at    compile    time;    if   you   \"use   Config\"   and\n$Config{'dunlinkallversions'} is \"define\", then \"unlink\" will delete all versions of a\nfile on the first call.)\n\n\"unlink\" will delete a file if at  all  possible,  even  if  it  requires  changing  file\nprotection  (though  it won't try to change the protection of the parent directory).  You\ncan  tell  whether  you've  got  explicit  delete  access  to  a  file   by   using   the\n\"VMS::Filespec::candelete\"  operator.   For  instance,  in  order to delete only files to\nwhich you have delete access, you could say something like\n\nsub safeunlink {\nmy($file,$num);\nforeach $file (@) {\nnext unless VMS::Filespec::candelete($file);\n$num += unlink $file;\n}\n$num;\n}\n\n(or you could just use \"VMS::Stdio::remove\", if you've installed the VMS::Stdio extension\ndistributed with Perl). If \"unlink\" has to change the file protection to delete the file,\nand you interrupt it in midstream, the file may be left intact, but with  a  changed  ACL\nallowing you delete access.\n\nThis behavior of \"unlink\" is to be compatible with POSIX behavior and not traditional VMS\nbehavior.\n\nutime LIST\nThis operator changes only the modification time of the file (VMS revision date) on ODS-2\nvolumes  and  ODS-5  volumes  without  access dates enabled. On ODS-5 volumes with access\ndates enabled, the true access time is modified.\n\nwaitpid PID,FLAGS\nIf PID is a subprocess started by a piped open() (see open), \"waitpid\" will wait for that\nsubprocess, and return its final status value in $?.  If PID is a subprocess  created  in\nsome  other way (e.g.  SPAWNed before Perl was invoked), \"waitpid\" will simply check once\nper second whether the process has completed, and return when it has.  (If PID  specifies\na  process  that isn't a subprocess of the current process, and you invoked Perl with the\n\"-w\" switch, a warning will be issued.)\n\nReturns PID on success, -1 on error.  The FLAGS argument is ignored in all cases.\n",
            "subsections": []
        },
        "Perl variables": {
            "content": "The following VMS-specific information applies to the indicated \"special\" Perl variables,  in\naddition  to the general information in perlvar.  Where there is a conflict, this information\ntakes precedence.\n\n%ENV\nThe operation of  the  %ENV  array  depends  on  the  translation  of  the  logical  name\nPERLENVTABLES.  If defined, it should be a search list, each element of which specifies\na   location  for  %ENV  elements.   If  you  tell  Perl  to  read  or  set  the  element\n\"$ENV{\"name\"}\", then Perl uses the translations of PERLENVTABLES as follows:\n\nCRTLENV\nThis string tells Perl to consult the CRTL's internal \"environ\"  array  of  key-value\npairs,  using  name as the key.  In most cases, this contains only a few keys, but if\nPerl was invoked via the C \"exec[lv]e()\" function, as is the case for  some  embedded\nPerl applications or when running under a shell such as GNV bash, the \"environ\" array\nmay have been populated by the calling program.\n\nCLISYM[LOCAL]\nA string beginning with \"CLISYM\"tells Perl to consult the CLI's symbol tables, using\nname  as  the  name of the symbol.  When reading an element of %ENV, the local symbol\ntable is scanned first,  followed  by  the  global  symbol  table..   The  characters\nfollowing \"CLISYM\" are significant when an element of %ENV is set or deleted: if the\ncomplete  string  is  \"CLISYMLOCAL\",  the  change is made in the local symbol table;\notherwise the global symbol table is changed.\n\nAny other string\nIf an element of PERLENVTABLES translates to any other string, that string is  used\nas  the  name  of  a logical name table, which is consulted using name as the logical\nname.  The normal search order of access modes is used.\n\nPERLENVTABLES is translated once when Perl starts up; any changes you make  while  Perl\nis  running  do not affect the behavior of %ENV.  If PERLENVTABLES is not defined, then\nPerl defaults to consulting first the logical name tables specified by LNM$FILEDEV,  and\nthen  the  CRTL  \"environ\"  array.   This default order is reversed when the logical name\nGNV$UNIXSHELL is defined, such as when running under GNV bash.\n\nFor operations on %ENV entries based on logical names or DCL symbols, the key  string  is\ntreated  as  if  it were entirely uppercase, regardless of the case actually specified in\nthe Perl expression. Entries in %ENV based on the CRTL's environ array preserve the  case\nof the key string when stored, and lookups are case sensitive.\n\nWhen  an  element  of  %ENV  is  read,  the locations to which PERLENVTABLES points are\nchecked in order, and the value obtained from the first successful  lookup  is  returned.\nIf the name of the %ENV element contains a semi-colon, it and any characters after it are\nremoved.   These  are  ignored  when  the  CRTL  \"environ\" array or a CLI symbol table is\nconsulted.  However, the name is looked up in a logical name table, the suffix after  the\nsemi-colon is treated as the translation index to be used for the lookup.   This lets you\nlook up successive values for search list logical names.  For instance, if you say\n\n$  Define STORY  once,upon,a,time,there,was\n$  perl -e \"for ($i = 0; $i <= 6; $i++) \" -\n$ -e \"{ print $ENV{'story;'.$i},' '}\"\n\nPerl  will  print \"ONCE UPON A TIME THERE WAS\", assuming, of course, that PERLENVTABLES\nis set up so that the logical name \"story\" is found, rather than a  CLI  symbol  or  CRTL\n\"environ\" element with the same name.\n\nWhen  an element of %ENV is set to a defined string, the corresponding definition is made\nin the location to which the first translation of PERLENVTABLES points.  If this causes\na logical name to be created, it is defined in supervisor mode.  (The same is done if  an\nexisting  logical  name  was  defined  in  executive  or kernel mode; an existing user or\nsupervisor mode logical name is reset to the new  value.)   If  the  value  is  an  empty\nstring,  the  logical  name's  translation  is  defined  as  a  single \"NUL\" (ASCII \"\\0\")\ncharacter, since a  logical  name  cannot  translate  to  a  zero-length  string.   (This\nrestriction  does  not apply to CLI symbols or CRTL \"environ\" values; they are set to the\nempty string.)\n\nWhen an element of %ENV is set to \"undef\", the element is looked up as if it  were  being\nread,  and  if  it  is  found, it is deleted.  (An item \"deleted\" from the CRTL \"environ\"\narray is set to the empty string.)  Using \"delete\" to remove an element from %ENV  has  a\nsimilar  effect, but after the element is deleted, another attempt is made to look up the\nelement, so an inner-mode logical name or a name in another  location  will  replace  the\nlogical  name  just  deleted.  In  either  case,  only  the  first  value found searching\nPERLENVTABLES is altered.  It is not possible  at  present  to  define  a  search  list\nlogical name via %ENV.\n\nThe element $ENV{DEFAULT} is special: when read, it returns Perl's current default device\nand   directory,  and  when  set,  it  resets  them,  regardless  of  the  definition  of\nPERLENVTABLES.  It cannot be cleared  or  deleted;  attempts  to  do  so  are  silently\nignored.\n\nNote  that  if  you  want  to  pass  on  any  elements  of the C-local environ array to a\nsubprocess which isn't started by fork/exec, or  isn't  running  a  C  program,  you  can\n\"promote\"  them  to logical names in the current process, which will then be inherited by\nall subprocesses, by saying\n\nforeach my $key (qw[C-local keys you want promoted]) {\nmy $temp = $ENV{$key}; # read from C-local array\n$ENV{$key} = $temp;    # and define as logical name\n}\n\n(You can't just say \"$ENV{$key} = $ENV{$key}\", since the Perl optimizer is  smart  enough\nto elide the expression.)\n\nDon't  try  to  clear  %ENV by saying \"%ENV = ();\", it will throw a fatal error.  This is\nequivalent to doing the following from DCL:\n\nDELETE/LOGICAL *\n\nYou can imagine how bad things would be if, for example, the  SYS$MANAGER  or  SYS$SYSTEM\nlogical names were deleted.\n\nAt  present,  the  first  time you iterate over %ENV using \"keys\", or \"values\",  you will\nincur a time penalty as all logical names are read, in  order  to  fully  populate  %ENV.\nSubsequent  iterations  will not reread logical names, so they won't be as slow, but they\nalso won't reflect any changes to logical name tables caused by other programs.\n\nYou do need to be careful with the logical names  representing  process-permanent  files,\nsuch  as  \"SYS$INPUT\"  and  \"SYS$OUTPUT\".   The  translations for these logical names are\nprepended with a two-byte binary value (0x1B 0x00) that needs to be stripped off  if  you\nwant  to  use  it.  (In previous versions of Perl it wasn't possible to get the values of\nthese logical names, as the null byte acted as an end-of-string marker)\n\n$!  The string value of $! is that returned by the CRTL's strerror()  function,  so  it  will\ninclude the VMS message for VMS-specific errors.  The numeric value of $! is the value of\n\"errno\",  except  if errno is EVMSERR, in which case $! contains the value of vaxc$errno.\nSetting $!  always sets errno to the value specified.  If this value is EVMSERR, it  also\nsets  vaxc$errno  to 4 (NONAME-F-NOMSG), so that the string value of $! won't reflect the\nVMS error message from before $! was set.\n\n$^E This variable provides direct access to VMS status values in vaxc$errno, which are  often\nmore specific than the generic Unix-style error messages in $!.  Its numeric value is the\nvalue  of  vaxc$errno,  and  its string value is the corresponding VMS message string, as\nretrieved by sys$getmsg().  Setting $^E sets vaxc$errno to the value specified.\n\nWhile Perl attempts to keep the vaxc$errno value to be current, if errno is not  EVMSERR,\nit may not be from the current operation.\n\n$?  The  \"status  value\"  returned  in  $?  is synthesized from the actual exit status of the\nsubprocess in a way that approximates POSIX wait(5) semantics, in  order  to  allow  Perl\nprograms  to  portably  test  for successful completion of subprocesses.  The low order 8\nbits of $? are always 0 under VMS, since the termination status of a process may  or  may\nnot have been generated by an exception.\n\nThe next 8 bits contain the termination status of the program.\n\nIf  the  child process follows the convention of C programs compiled with the POSIXEXIT\nmacro set, the status value will contain the actual value of 0 to 255  returned  by  that\nprogram on a normal exit.\n\nWith  the  POSIXEXIT  macro  set,  the  Unix exit value of zero is represented as a VMS\nnative status of 1, and the Unix values from 2 to 255 are encoded by the equation:\n\nVMSstatus = 0x35a000 + (unixvalue * 8) + 1.\n\nAnd in the special case of Unix value 1 the encoding is:\n\nVMSstatus = 0x35a000 + 8 + 2 + 0x10000000.\n\nFor other termination statuses, the severity portion of the subprocess's exit  status  is\nused: if the severity was success or informational, these bits are all 0; if the severity\nwas  warning,  they  contain a value of 1; if the severity was error or fatal error, they\ncontain the actual severity bits, which turns out to be a value of 2 for error and 4  for\nsevereerror.  Fatal is another term for the severeerror status.\n\nAs  a result, $? will always be zero if the subprocess's exit status indicated successful\ncompletion, and non-zero if a warning or error  occurred  or  a  program  compliant  with\nencoding POSIXEXIT values was run and set a status.\n\nHow  can  you  tell  the difference between a non-zero status that is the result of a VMS\nnative error status or an encoded Unix status?  You  can  not  unless  you  look  at  the\n${^CHILDERRORNATIVE}  value.   The  ${^CHILDERRORNATIVE} value returns the actual VMS\nstatus value and check the severity bits. If the severity bits are equal to  1,  then  if\nthe  numeric  value for $? is between 2 and 255 or 0, then $? accurately reflects a value\npassed back from a Unix application.  If $? is 1, and the severity bits  indicate  a  VMS\nerror (2), then $? is from a Unix application exit value.\n\nIn  practice,  Perl scripts that call programs that return POSIXEXIT type status values\nwill be expecting those values, and programs that  call  traditional  VMS  programs  will\neither be expecting the previous behavior or just checking for a non-zero status.\n\nAnd success is always the value 0 in all behaviors.\n\nWhen  the actual VMS termination status of the child is an error, internally the $! value\nwill be set to the closest Unix errno value to that error so that Perl scripts that  test\nfor  error  messages  will  see  the  expected  Unix style error message instead of a VMS\nmessage.\n\nConversely, when setting $? in an END block, an attempt is  made  to  convert  the  POSIX\nvalue  into a native status intelligible to the operating system upon exiting Perl.  What\nthis boils down to is that setting $? to  zero  results  in  the  generic  success  value\nSS$NORMAL,  and  setting  $?  to  a non-zero value results in the generic failure status\nSS$ABORT.  See also \"exit\" in perlport.\n\nWith the \"PERLVMSPOSIXEXIT\" logical name defined as \"ENABLE\", setting  $?  will  cause\nthe  new  value  to  be encoded into $^E so that either the original parent or child exit\nstatus values\n0 to 255 can be automatically recovered by C programs  expecting  POSIXEXIT  behavior.\nIf  both  a parent and a child exit value are non-zero, then it will be assumed that this\nis actually a VMS native status value to be passed through.  The special value of  0xFFFF\nis  almost  a  NOOP  as  it  will cause the current native VMS status in the C library to\nbecome the current native Perl VMS status, and is handled this way as it is known to  not\nbe  a  valid  native  VMS status value.  It is recommend that only values in the range of\nnormal Unix parent or child status numbers, 0 to 255 are used.\n\nThe pragma \"use vmsish 'status'\" makes $? reflect the actual VMS exit status  instead  of\nthe  default  emulation  of  POSIX status described above.  This pragma also disables the\nconversion of non-zero values to SS$ABORT when setting $? in an END block (but zero will\nstill be converted to SS$NORMAL).\n\nDo not use the pragma \"use vmsish 'status'\" with \"PERLVMSPOSIXEXIT\" enabled,  as  they\nare  at  times requesting conflicting actions and the consequence of ignoring this advice\nwill be undefined to allow future improvements in the POSIX exit handling.\n\nIn general,  with  \"PERLVMSPOSIXEXIT\"  enabled,  more  detailed  information  will  be\navailable in the exit status for DCL scripts or other native VMS tools, and will give the\nexpected  information  for  Posix programs.  It has not been made the default in order to\npreserve backward compatibility.\n\nN.B. Setting \"DECC$FILENAMEUNIXREPORT\" implicitly enables \"PERLVMSPOSIXEXIT\".\n\n$|  Setting $| for an I/O stream causes data to be flushed all the way to disk on each  write\n(i.e.  not  just  to  the  underlying  RMS  buffers  for  a  file).  In other words, it's\nequivalent to calling fflush() and fsync() from C.\n",
            "subsections": []
        },
        "Standard modules with VMS-specific differences": {
            "content": "",
            "subsections": [
                {
                    "name": "SDBM_File",
                    "content": "SDBMFile works properly on  VMS.  It  has,  however,  one  minor  difference.  The  database\ndirectory file created has a .sdbmdir extension rather than a .dir extension. .dir files are\nVMS  filesystem  directory  files, and using them for other purposes could cause unacceptable\nproblems.\n"
                }
            ]
        },
        "Revision date": {
            "content": "Please see the git repository for revision history.\n",
            "subsections": []
        },
        "AUTHOR": {
            "content": "Charles Bailey  bailey@cor.newman.upenn.edu  Craig  Berry   craigberry@mac.com  Dan  Sugalski\ndan@sidhe.org John Malmberg wb8tyw@qsl.net\n\nperl v5.38.2                                 2026-08-18                                   PERLVMS(1)",
            "subsections": []
        }
    },
    "summary": "perlvms - VMS-specific documentation for Perl",
    "flags": [],
    "examples": [],
    "see_also": []
}