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perldos (1)


perldos - Perl under DOS, W31, W95.


These are instructions for building Perl under DOS (or w??),
using DJGPP v2.03 or later.  Under w95 long filenames are


Perl Programmers Reference Guide                       PERLDOS(1)

     perldos - Perl under DOS, W31, W95.

     These are instructions for building Perl under DOS (or w??),
     using DJGPP v2.03 or later.  Under w95 long filenames are

     Before you start, you should glance through the README file
     found in the top-level directory where the Perl distribution
     was extracted.  Make sure you read and understand the terms
     under which this software is being distributed.

     This port currently supports MakeMaker (the set of modules
     that is used to build extensions to perl).  Therefore, you
     should be able to build and install most extensions found in
     the CPAN sites.

     Detailed instructions on how to build and install perl
     extension modules, including XS-type modules, is included.

  Prerequisites for Compiling Perl on DOS
         DJGPP is a port of GNU C/C++ compiler and development
         tools to 32-bit, protected-mode environment on Intel
         32-bit CPUs running MS-DOS and compatible operating
         systems, by DJ Delorie <> and friends.

         For more details (FAQ), check out the home of DJGPP at:


         If you have questions about DJGPP, try posting to the
         DJGPP newsgroup: comp.os.msdos.djgpp, or use the email

         You can find the full DJGPP distribution on any of the
         mirrors listed here:


         You need the following files to build perl (or add new

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         or possibly any newer version.

         Thread support is not tested in this version of the
         djgpp perl.

  Shortcomings of Perl under DOS
     Perl under DOS lacks some features of perl under UNIX
     because of deficiencies in the UNIX-emulation, most notably:

     o   fork() and pipe()

     o   some features of the UNIX filesystem regarding link
         count and file dates

     o   in-place operation is a little bit broken with short

     o   sockets

  Building Perl on DOS
     o   Unpack the source package perl5.8*.tar.gz with djtarx.
         If you want to use long file names under w95 and also to
         get Perl to pass all its tests, don't forget to use

                 set LFN=y
                 set FNCASE=y

         before unpacking the archive.

     o   Create a "symlink" or copy your bash.exe to sh.exe in
         your "($DJDIR)/bin" directory.

                 ln -s bash.exe sh.exe

         [If you have the recommended version of bash for DJGPP,
         this is already done for you.]

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         And make the "SHELL" environment variable point to this

                 set SHELL=c:/djgpp/bin/sh.exe (use full path name!)

         You can do this in djgpp.env too. Add this line BEFORE
         any section definition:


     o   If you have split.exe and gsplit.exe in your path, then
         rename split.exe to djsplit.exe, and gsplit.exe to
         split.exe.  Copy or link gecho.exe to echo.exe if you
         don't have echo.exe.  Copy or link gawk.exe to awk.exe
         if you don't have awk.exe.

         [If you have the recommended versions of djdev, shell
         utilities and gawk, all these are already done for you,
         and you will not need to do anything.]

     o   Chdir to the djgpp subdirectory of perl toplevel and
         type the following commands:

                 set FNCASE=y

         This will do some preprocessing then run the Configure
         script for you.  The Configure script is interactive,
         but in most cases you just need to press ENTER.  The
         "set" command ensures that DJGPP preserves the letter
         case of file names when reading directories.  If you
         already issued this set command when unpacking the
         archive, and you are in the same DOS session as when you
         unpacked the archive, you don't have to issue the set
         command again.  This command is necessary *before* you
         start to (re)configure or (re)build perl in order to
         ensure both that perl builds correctly and that building
         XS-type modules can succeed.  See the DJGPP info entry
         for "_preserve_fncase" for more information:

                 info libc alphabetical _preserve_fncase

         If the script says that your package is incomplete, and
         asks whether to continue, just answer with Y (this can
         only happen if you don't use long filenames or forget to
         issue "set FNCASE=y" first).

         When Configure asks about the extensions, I suggest IO
         and Fcntl, and if you want database handling then
         SDBM_File or GDBM_File (you need to install gdbm for
         this one). If you want to use the POSIX extension (this
         is the default), make sure that the stack size of your

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         cc1.exe is at least 512kbyte (you can check this with:
         "stubedit cc1.exe").

         You can use the Configure script in non-interactive mode
         too.  When I built my perl.exe, I used something like

                 configure.bat -des

         You can find more info about Configure's command line
         switches in the INSTALL file.

         When the script ends, and you want to change some values
         in the generated file, then run

                 sh Configure -S

         after you made your modifications.

         IMPORTANT: if you use this "-S" switch, be sure to
         delete the CONFIG environment variable before running
         the script:

                 set CONFIG=

     o   Now you can compile Perl. Type:


  Testing Perl on DOS

             make test

     If you're lucky you should see "All tests successful". But
     there can be a few failed subtests (less than 5 hopefully)
     depending on some external conditions (e.g. some subtests
     fail under linux/dosemu or plain dos with short filenames

  Installation of Perl on DOS

             make install

     This will copy the newly compiled perl and libraries into
     your DJGPP directory structure. Perl.exe and the utilities
     go into "($DJDIR)/bin", and the library goes under
     "($DJDIR)/lib/perl5". The pod documentation goes under

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  Building Prerequisites for Perl on DOS
     For building and installing non-XS modules, all you need is
     a working perl under DJGPP.  Non-XS modules do not require
     re-linking the perl binary, and so are simpler to build and

     XS-type modules do require re-linking the perl binary,
     because part of an XS module is written in "C", and has to
     be linked together with the perl binary to be executed.
     This is required because perl under DJGPP is built with the
     "static link" option, due to the lack of "dynamic linking"
     in the DJGPP environment.

     Because XS modules require re-linking of the perl binary,
     you need both the perl binary distribution and the perl
     source distribution to build an XS extension module.  In
     addition, you will have to have built your perl binary from
     the source distribution so that all of the components of the
     perl binary are available for the required link step.

  Unpacking CPAN Modules on DOS
     First, download the module package from CPAN (e.g., the
     "Comma Separated Value" text package, Text-CSV-0.01.tar.gz).
     Then expand the contents of the package into some location
     on your disk.  Most CPAN modules are built with an internal
     directory structure, so it is usually safe to expand it in
     the root of your DJGPP installation.  Some people prefer to
     locate source trees under /usr/src (i.e.,
     "($DJDIR)/usr/src"), but you may put it wherever seems most
     logical to you, *EXCEPT* under the same directory as your
     perl source code.  There are special rules that apply to
     modules which live in the perl source tree that do not apply
     to most of the modules in CPAN.

     Unlike other DJGPP packages, which are normal "zip" files,
     most CPAN module packages are "gzipped tarballs".  Recent
     versions of WinZip will safely unpack and expand them,
     *UNLESS* they have zero-length files.  It is a known WinZip
     bug (as of v7.0) that it will not extract zero-length files.

     From the command line, you can use the djtar utility
     provided with DJGPP to unpack and expand these files.  For

             C:\djgpp>djtarx -v Text-CSV-0.01.tar.gz

     This will create the new directory "($DJDIR)/Text-CSV-0.01",
     filling it with the source for this module.

  Building Non-XS Modules on DOS
     To build a non-XS module, you can use the standard module-

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     building instructions distributed with perl modules.

         perl Makefile.PL
         make test
         make install

     This is sufficient because non-XS modules install only ".pm"
     files and (sometimes) pod and/or man documentation.  No re-
     linking of the perl binary is needed to build, install or
     use non-XS modules.

  Building XS Modules on DOS
     To build an XS module, you must use the standard module-
     building instructions distributed with perl modules *PLUS*
     three extra instructions specific to the DJGPP "static link"
     build environment.

         set FNCASE=y
         perl Makefile.PL
         make perl
         make test
         make -f Makefile.aperl inst_perl MAP_TARGET=perl.exe
         make install

     The first extra instruction sets DJGPP's FNCASE environment
     variable so that the new perl binary which you must build
     for an XS-type module will build correctly.  The second
     extra instruction re-builds the perl binary in your module
     directory before you run "make test", so that you are
     testing with the new module code you built with "make".  The
     third extra instruction installs the perl binary from your
     module directory into the standard DJGPP binary directory,
     "($DJDIR)/bin", replacing your previous perl binary.

     Note that the MAP_TARGET value *must* have the ".exe"
     extension or you will not create a "perl.exe" to replace the
     one in "($DJDIR)/bin".

     When you are done, the XS-module install process will have
     added information to your "perllocal" information telling
     that the perl binary has been replaced, and what module was
     installed.  You can view this information at any time by
     using the command:

             perl -S perldoc perllocal

     Laszlo Molnar,
     [Installing/building perl]

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     Peter J. Farley III [Building/installing

     See attributes(5) for descriptions of the following

     |Availability   | runtime/perl-512 |
     |Stability      | Uncommitted      |

     This software was built from source available at  The original
     community source was downloaded from

     Further information about this software can be found on the
     open source community website at

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