ExtUtils::Liblist - determine libraries to use and how to use them
This utility takes a list of libraries in the form
-llib1 -llib2 -llib3 and prints out lines suitable for inclusion in an extension Makefile.
Extra library paths may be included with the form
-L/another/path this will affect the searches for all subsequent libraries.
It returns an array of four scalar values: EXTRALIBS, BSLOADLIBS, LDLOADLIBS, and LD_RUN_PATH.
Dependent libraries can be linked in one of three ways:
by the ld command when the perl binary is linked with the extension library. See EXTRALIBS below.
by the ld command when the shared object is built/linked. See LDLOADLIBS below.
by the DynaLoader when the shared object is loaded. See BSLOADLIBS below.
List of libraries that need to be linked with when linking a perl binary which includes this extension Only those libraries that actually exist are included. These are written to a file and used when linking perl.
List of those libraries which can or must be linked into the shared library when created using ld. These may be static or dynamic libraries. LD_RUN_PATH is a colon separated list of the directories in LDLOADLIBS. It is passed as an environment variable to the process that links the shared library.
List of those libraries that are needed but can be linked in dynamically at run time on this platform. SunOS/Solaris does not need this because ld records the information (from LDLOADLIBS) into the object file. This list is used to create a .bs (bootstrap) file.
This module deals with a lot of system dependencies and has quite a few architecture specific ifs in the code.
The version of ext() which is executed under VMS differs from the Unix-OS/2 version in several respects:
-Lprefices used by Unix linkers. If neither prefix is present, a token is considered a directory to search if it is in fact a directory, and a library to search for otherwise. Authors who wish their extensions to be portable to Unix or OS/2 should use the Unix prefixes, since the Unix-OS/2 version of ext() requires them.
In addition, an attempt is made to recognize several common Unix library names, and filter them out or convert them to their VMS equivalents, as appropriate.
In general, the VMS version of ext() should properly handle input from extensions originally designed for a Unix or VMS environment. If you encounter problems, or discover cases where the search could be improved, please let us know.