How do I add a directory to my include path (@INC) at runtime?

Here are the suggested ways of modifying your include path, including environment variables, run-time switches, and in-code statements:

  • the PERLLIB environment variable
    	$ export PERLLIB=/path/to/my/dir
    	$ perl
  • the PERL5LIB environment variable
    	$ export PERL5LIB=/path/to/my/dir
    	$ perl
  • the perl -Idir command line flag
    	$ perl -I/path/to/my/dir
  • the use lib pragma:
    	use lib "$ENV{HOME}/myown_perllib";

The last is particularly useful because it knows about machine dependent architectures. The pragmatic module was first included with the 5.002 release of Perl.