Build And Installation Guide For PERL5


Install - Build and Installation guide for perl5.


The basic steps to build and install perl5 are:

	rm -f
	sh Configure
	make test
	make install

Each of these is explained in further detail below.


Start with a Fresh Distribution.

The results of a Configure run are stored in the file. If you are upgrading from a previous version of perl, or if you change systems or compilers or make other significant changes, or if you are experiencing difficulties building perl, you should probably not re-use your old Simply remove it or rename it, e.g.


Then run Configure.

Run Configure.

Configure will figure out various things about your system. Some things Configure will figure out for itself, other things it will ask you about. To accept the default, just press RETURN. The default is almost always ok.

After it runs, Configure will perform variable substitution on all the *.SH files and offer to run make depend .

Configure supports a number of useful options. Run Configure -h to get a listing. To compile with gcc, for example, you can run

	sh Configure -Dcc=gcc

This is the preferred way to specify gcc (or another alternative compiler) so that the hints files can set appropriate defaults.

If you want to use your old but override some of the items with command line options, you need to use Configure -O .

If you are willing to accept all the defaults, and you want terse output, you can run

	sh Configure -des

By default, for most systems, perl will be installed in /usr/local/{bin, lib, man}. You can specify a different 'prefix' for the default installation directory, when Configure prompts you or by using the Configure command line option -Dprefix='/some/directory', e.g.

	sh Configure -Dprefix=/opt/perl

If your prefix contains the string ``perl'', then the directories are simplified. For example, if you use prefix=/opt/perl, then Configure will suggest /opt/perl/lib instead of /usr/local/lib/perl5/.

By default, Configure will compile perl to use dynamic loading, if your system supports it. If you want to force perl to be compiled statically, you can either choose this when Configure prompts you or by using the Configure command line option -Uusedl.


By default, Configure will offer to build every extension which appears to be supported. For example, Configure will offer to build GDBM_File only if it is able to find the gdbm library. (See examples below.) DynaLoader and Fcntl are always built by default. Configure does not contain code to test for POSIX compliance, so POSIX is always built by default as well. If you wish to skip POSIX, you can set the Configure variable useposix=false either in a hint file or from the Configure command line. Similarly, the Safe extension is always built by default, but you can skip it by setting the Configure variable usesafe=false either in a hint file for from the command line.

In summary, here are the Configure command-line variables you can set to turn off each extension:

    DB_File		i_db
    DynaLoader		(Must always be included)
    Fcntl		(Always included by default)
    GDBM_File		i_gdbm
    NDBM_File		i_ndbm
    ODBM_File		i_dbm
    POSIX		useposix
    SDBM_File		(Always included by default)
    Safe		usesafe
    Socket		d_socket

Thus to skip the NDBM_File extension, you can use

	sh Configure -Ui_ndbm

Again, this is taken care of automatically if you don't have the ndbm library.

Of course, you may always run Configure interactively and select only the Extensions you want.

Finally, if you have dynamic loading (most modern Unix systems do) remember that these extensions do not increase the size of your perl executable, nor do they impact start-up time, so you probably might as well build all the ones that will work on your system.

GNU-style configure

If you prefer the GNU-style configure command line interface, you can use the supplied configure command, e.g.

	CC=gcc ./configure

The configure script emulates several of the more common configure options. Try

	./configure --help

for a listing.

Cross compiling is currently not supported.

Including locally-installed libraries

Perl5 comes with interfaces to number of database extensions, including dbm, ndbm, gdbm, and Berkeley db. For each extension, if Configure can find the appropriate header files and libraries, it will automatically include that extension. The gdbm and db libraries are not included with perl. See the library documentation for how to obtain the libraries.

Note: If your database header (.h) files are not in a directory normally searched by your C compiler, then you will need to include the appropriate -I/your/directory option when prompted by Configure. If your database library (.a) files are not in a directory normally searched by your C compiler and linker, then you will need to include the appropriate -L/your/directory option when prompted by Configure. See the examples below.


gdbm in /usr/local.
Suppose you have gdbm and want Configure to find it and build the GDBM_File extension. This examples assumes you have gdbm.h installed in /usr/local/include/gdbm.h and libgdbm.a installed in /usr/local/lib/libgdbm.a . Configure should figure all the necessary steps out automatically.

Specifically, when Configure prompts you for flags for your C compiler, you should include -I/usr/local/include.

When Configure prompts you for linker flags, you should include -L/usr/local/lib.

If you are using dynamic loading, then when Configure prompts you for linker flags for dynamic loading, you should again include -L/usr/local/lib.

Again, this should all happen automatically. If you want to accept the defaults for all the questions and have Configure print out only terse messages, then you can just run

	sh Configure -des

and Configure should include the GDBM_File extension automatically.

This should actually work if you have gdbm installed in any of (/usr/local, /opt/local, /usr/gnu, /opt/gnu, /usr/GNU, or /opt/GNU).

gdbm in /usr/you
Suppose you have gdbm installed in some place other than /usr/local/, but you still want Configure to find it. To be specific, assume you have /usr/you/include/gdbm.h and /usr/you/lib/libgdbm.a . You still have to add -I/usr/you/include to cc flags, but you have to take an extra step to help Configure find libgdbm.a . Specifically, when Configure prompts you for library directories, you have to add /usr/you/lib to the list.

It is possible to specify this from the command line too (all on one line):

	sh Configure -des \
		-Dlocincpth="/usr/you/include" \

locincpth is a space-separated list of include directories to search. Configure will automatically add the appropriate -I directives.

loclibpth is a space-separated list of library directories to search. Configure will automatically add the appropriate -L directives. If you have some libraries under /usr/local/ and others under /usr/you , then you have to include both, namely

	sh Configure -des \
		-Dlocincpth="/usr/you/include /usr/local/include" \
		-Dloclibpth="/usr/you/lib /usr/local/lib"

Installation Directories.

The installation directories can all be changed by answering the appropriate questions in Configure. For convenience, all the installation questions are near the beginning of Configure.

By default, Configure uses the following directories for library files (archname is a string like sun4-sunos, determined by Configure)


and the following directories for manual pages:


(Actually, Configure recognizes the SVR3-style /usr/local/man/l_man/man1 directories, if present, and uses those instead.) The module man pages are stuck in that strange spot so that they don't collide with other man pages stored in /usr/local/man/man3, and so that Perl's man pages don't hide system man pages. On some systems, man less would end up calling up Perl's module man page, rather than the less program.

If you specify a prefix that contains the string ``perl'', then the directory structure is simplified. For example, if you Configure with -Dprefix=/opt/perl, then the defaults are



The perl executable will search the libraries in the order given above.

The directories site_perl and site_perl/archname are empty, but are intended to be used for installing local or site-wide extensions. Perl will automatically look in these directories. Previously, most sites just put their local extensions in with the standard distribution.

In order to support using things like #!/usr/local/bin/perl5.002 after a later version is released, architecture-dependent libraries are stored in a version-specific directory, such as /usr/local/lib/perl5/archname/5.002/. In 5.000 and 5.001, these files were just stored in /usr/local/lib/perl5/archname/. If you will not be using 5.001 binaries, you can delete the standard extensions from the /usr/local/lib/perl5/archname/ directory. Locally-added extensions can be moved to the site_perl and site_perl/archname directories.

Again, these are just the defaults, and can be changed as you run Configure.

Changing the installation directory

Configure distinguishes between the directory in which perl (and its associated files) should be installed and the directory in which it will eventually reside. For most sites, these two are the same; for sites that use AFS, this distinction is handled automatically. However, sites that use software such as depot to manage software packages may also wish to install perl into a different directory and use that management software to move perl to its final destination. This section describes how to do this. Someday, Configure may support an option -Dinstallprefix=/foo to simplify this.

Suppose you want to install perl under the /tmp/perl5 directory. You can edit and change all the install* variables to point to /tmp/perl5 instead of /usr/local/wherever . You could also set them all from the Configure command line. Or, you can automate this process by placing the following lines in a file config.over before you run Configure (replace /tmp/perl5 by a directory of your choice):

    test -d $installprefix || mkdir $installprefix
    test -d $installprefix/bin || mkdir $installprefix/bin
    installarchlib=`echo $installarchlib | sed "s!$prefix!$installprefix!"`
    installbin=`echo $installbin | sed "s!$prefix!$installprefix!"`
    installman1dir=`echo $installman1dir | sed "s!$prefix!$installprefix!"`
    installman3dir=`echo $installman3dir | sed "s!$prefix!$installprefix!"`
    installprivlib=`echo $installprivlib | sed "s!$prefix!$installprefix!"`
    installscript=`echo $installscript | sed "s!$prefix!$installprefix!"`
    installsitelib=`echo $installsitelib | sed "s!$prefix!$installprefix!"`
    installsitearch=`echo $installsitearch | sed "s!$prefix!$installprefix!"`

Then, you can Configure and install in the usual way:

    sh Configure -des
    make test
    make install

Creating an installable tar archive

If you need to install perl on many identical systems, it is convenient to compile it once and create an archive that can be installed on multiple systems. Here's one way to do that:

    # Set up config.over to install perl into a different directory,
    # e.g. /tmp/perl5 (see previous part).
    sh Configure -des
    make test
    make install
    cd /tmp/perl5
    tar cvf ../perl5-archive.tar .
    # Then, on each machine where you want to install perl,
    cd /usr/local  # Or wherever you specified as $prefix
    tar xvf perl5-archive.tar

What if it doesn't work?

Running Configure Interactively
If Configure runs into trouble, remember that you can always run Configure interactively so that you can check (and correct) its guesses.

All the installation questions have been moved to the top, so you don't have to wait for them. Once you've handled them (and your C compiler & flags) you can type '&-d' at the next Configure prompt and Configure will use the defaults from then on.

If you find yourself trying obscure command line incantations and config.over tricks, I recommend you run Configure interactively instead. You'll probably save yourself time in the long run.

Hint files.
The perl distribution includes a number of system-specific hints files in the hints/ directory. If one of them matches your system, Configure will offer to use that hint file.

Several of the hint files contain additional important information. If you have any problems, it is a good idea to read the relevant hint file for further information. See hints/ for an extensive example.

Changing Compilers
If you change compilers or make other significant changes, you should probably not re-use your old Simply remove it or rename it, e.g. mv Then rerun Configure with the options you want to use.

This is a common source of problems. If you change from cc to gcc , you should almost always remove your old

Propagating your changes
If you later make any changes to , you should propagate them to all the .SH files by running sh Configure -S .

You can also supply a shell script config.over to over-ride Configure's guesses. It will get loaded up at the very end, just before is created. You have to be careful with this, however, as Configure does no checking that your changes make sense. See the section on changing the installation directory for an example.

Many of the system dependencies are contained in config.h . Configure builds config.h by running the config_h.SH script. The values for the variables are taken from .

If there are any problems, you can edit config.h directly. Beware, though, that the next time you run Configure , your changes will be lost.

If you have any additional changes to make to the C compiler command line, they can be made in cflags.SH . For instance, to turn off the optimizer on toke.c , find the line in the switch structure for toke.c and put the command optimize='-g' before the ;;. You can also edit cflags directly, but beware that your changes will be lost the next time you run Configure .

To change the C flags for all the files, edit and change either $ccflags or $optimize, and then re-run sh Configure -S ; make depend .

No sh.
If you don't have sh, you'll have to copy the sample file config_H to config.h and edit the config.h to reflect your system's peculiarities. You'll probably also have to extensively modify the extension building mechanism.

make depend

This will look for all the includes. The output is stored in makefile . The only difference between Makefile and makefile is the dependencies at the bottom of makefile . If you have to make any changes, you should edit makefile , not Makefile since the Unix make command reads makefile first.

Configure will offer to do this step for you, so it isn't listed explicitly above.


This will attempt to make perl in the current directory.

If you can't compile successfully, try some of the following ideas.

make test

This will run the regression tests on the perl you just made. If it doesn't say ``All tests successful'' then something went wrong. See the file t/README in the t subdirectory. Note that you can't run it in background if this disables opening of /dev/tty. If make test bombs out, just cd to the t directory and run TEST by hand to see if it makes any difference. If individual tests bomb, you can run them by hand, e.g.,

	./perl op/groups.t

NOTE : one possible reason for errors is that some external programs may be broken due to the combination of your environment and the way make test exercises them. This may happen for example if you have one or more of these environment variables set: LC_ALL LC_CTYPE LANG. In certain UNIXes especially the non-English locales are known to cause programs to exhibit mysterious errors. If you have any of the above environment variables set, please try setenv LC_ALL C or LC_ALL=C;export LC_ALL>, for csh-style and Bourne-style shells, respectively, from the command line and then retry make test. If the tests then succeed, you may have a broken program that is confusing the testing. Please run the troublesome test by hand as shown above and see whether you can locate the program. Look for things like: exec, `backquoted command`, system, open("|...") or open("...|"). All these mean that Perl is trying to run some external program.

make install

This will put perl into the public directory you specified to Configure ; by default this is /usr/local/bin . It will also try to put the man pages in a reasonable place. It will not nroff the man page, however. You may need to be root to run make install . If you are not root, you must own the directories in question and you should ignore any messages about chown not working.

If you want to see exactly what will happen without installing anything, you can run

	./perl installperl -n
	./perl installman -n

make install will install the following:

	    perl5.nnn	where nnn is the current release number.  This
			will be a link to perl.
	    sperl5.nnn	If you requested setuid emulation.
	a2p          	awk-to-perl translator
	cppstdin	This is used by perl -P, if your cc -E can't
			read from stdin.
	c2ph, pstruct	Scripts for handling C structures in header files.
	s2p		sed-to-perl translator
	find2perl	find-to-perl translator
	h2xs		Converts C .h header files to Perl extensions.
	perlbug		Tool to report bugs in Perl.
	perldoc		Tool to read perl's pod documentation.
	pod2html,	Converters from perl's pod documentation format
	pod2latex, and 	to other useful formats.

	library files	in $privlib and $archlib specified to
			Configure, usually under /usr/local/lib/perl5/.
	man pages	in the location specified to Configure, usually
			something like /usr/local/man/man1.
	module		in the location specified to Configure, usually
	man pages	under /usr/local/lib/perl5/man/man3.
	pod/*.pod	in $privlib/pod/.

Installperl will also create the library directories $siteperl and $sitearch listed in Usually, these are something like /usr/local/lib/perl5/site_perl/ /usr/local/lib/perl5/site_perl/$archname where $archname is something like sun4-sunos. These directories will be used for installing extensions.

Perl's *.h header files and the libperl.a library are also installed under $archlib so that any user may later build new extensions even if the Perl source is no longer available.

The libperl.a library is only needed for building new extensions and linking them statically into a new perl executable. If you will not be doing that, then you may safely delete $archlib/libperl.a after perl is installed.

make install may also offer to install perl in a ``standard'' location.

Most of the documentation in the pod/ directory is also available in HTML and LaTeX format. Type

	cd pod; make html; cd ..

to generate the html versions, and

	cd pod; make tex; cd ..

to generate the LaTeX versions.

Coexistence with earlier versions of perl5.

You can safely install the current version of perl5 and still run scripts under the old binaries. Instead of starting your script with #!/usr/local/bin/perl, just start it with #!/usr/local/bin/perl5.001 (or whatever version you want to run.)

The architecture-dependent files are stored in a version-specific directory (such as /usr/local/lib/perl5/sun4-sunos/5.002 ) so that they are still accessible. Note: perl5.000 and perl5.001 did not put their architecture-dependent libraries in a version-specific directory. They are simply in /usr/local/lib/perl5/$archname . If you will not be using 5.000 or 5.001, you may safely remove those files.

The standard library files in /usr/local/lib/perl5 should be useable by all versions of perl5.

Most extensions will probably not need to be recompiled to use with a newer version of perl. If you do run into problems, and you want to continue to use the old version of perl along with your extension, simply move those extension files to the appropriate version directory, such as /usr/local/lib/perl/archname/5.002 . Then perl5.002 will find your files in the 5.002 directory, and newer versions of perl will find your newer extension in the site_perl directory.

Some users may prefer to keep all versions of perl in completely separate directories. One convenient way to do this is by using a separate prefix for each version, such as

	sh Configure -Dprefix=/opt/perl5.002

and adding /opt/perl5.002/bin to the shell PATH variable. Such users may also wish to add a symbolic link /usr/local/bin/perl so that scripts can still start with #!/usr/local/bin/perl.

Coexistence with perl4

You can safely install perl5 even if you want to keep perl4 around.

By default, the perl5 libraries go into /usr/local/lib/perl5/ , so they don't override the perl4 libraries in /usr/local/lib/perl/ .

In your /usr/local/bin directory, you should have a binary named perl4.036 . That will not be touched by the perl5 installation process. Most perl4 scripts should run just fine under perl5. However, if you have any scripts that require perl4, you can replace the #! line at the top of them by #!/usr/local/bin/perl4.036 (or whatever the appropriate pathname is).


Read the manual entries before running perl. The main documentation is in the pod/ subdirectory and should have been installed during the build process. Type man perl to get started. Alternatively, you can type perldoc perl to use the supplied perldoc script. This is sometimes useful for finding things in the library modules.


Andy Dougherty borrowing very heavily from the original README by Larry Wall.


04 January 1996