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 <email@example.com> and
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 firstname.lastname@example.org.
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:
- fork() and pipe()
- some features of the UNIX filesystem regarding link count and file
- in-place operation is a little bit broken with short filenames
Building Perl on DOS¶
- 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
before unpacking the archive.
- Create a "symlink" or copy your bash.exe to sh.exe in your
ln -s bash.exe sh.exe
[If you have the recommended version of bash for DJGPP, this is already done
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
- 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
- Chdir to the djgpp subdirectory of perl toplevel and type the following
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 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 this:
You can find more info about Configure's command line switches in the
When the script ends, and you want to change some values in the generated
config.sh 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:
- Now you can compile Perl. Type:
Testing Perl on DOS¶
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
Installation of Perl on DOS¶
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 "($DJDIR)/lib/perl5/pod".
BUILDING AND INSTALLING MODULES ON DOS¶
Building Prerequisites for Perl on DOS¶
For building and installing non-XS modules, all you need is a working perl under
DJGPP. Non-XS modules do not require re-linking the perl binary, and so are
simpler to build and install.
XS-type modules do require re-linking the perl binary, because part of an XS
module is written in "C", and has to be linked together with the
perl binary to be executed. This is required because perl under DJGPP is built
with the "static link" option, due to the lack of "dynamic
linking" in the DJGPP environment.
Because XS modules require re-linking of the perl binary, you need both the perl
binary distribution and the perl source distribution to build an XS extension
module. In addition, you will have to have built your perl binary from the
source distribution so that all of the components of the perl binary are
available for the required link step.
Unpacking CPAN Modules on DOS¶
First, download the module package from CPAN (e.g., the "Comma Separated
Value" text package, Text-CSV-0.01.tar.gz). Then expand the contents of
the package into some location on your disk. Most CPAN modules are built with
an internal directory structure, so it is usually safe to expand it in the
root of your DJGPP installation. Some people prefer to locate source trees
under /usr/src (i.e., "($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 "($DJDIR)/Text-CSV-0.01", filling
it with the source for this module.
Building Non-XS Modules on DOS¶
To build a non-XS module, you can use the standard module-building instructions
distributed with perl modules.
This is sufficient because non-XS modules install only ".pm" files and
(sometimes) pod and/or man documentation. No re-linking of the perl binary is
needed to build, install or use non-XS modules.
Building XS Modules on DOS¶
To build an XS module, you must use the standard module-building instructions
distributed with perl modules *PLUS* three extra instructions specific to the
DJGPP "static link" build environment.
make -f Makefile.aperl inst_perl MAP_TARGET=perl.exe
The first extra instruction sets DJGPP's FNCASE environment variable so that the
new perl binary which you must build for an XS-type module will build
correctly. The second extra instruction re-builds the perl binary in your
module directory before you run "make test", so that you are testing
with the new module code you built with "make". The third extra
instruction installs the perl binary from your module directory into the
standard DJGPP binary directory, "($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
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, email@example.com
Peter J. Farley III firstname.lastname@example.org