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 supported.


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. See 'BUILDING AND INSTALLING MODULES'.

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 gateway

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 modules):


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:

Building Perl on DOS

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 only).

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 ($DJDIR)/lib/perl5/pod.


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 install.

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 example:

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-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]

Peter J. Farley III [Building/installing modules]