REQUIREMENTS PRE-INSTALL POST-INSTALL PRECAUTION pcre means Perl Compatible Regular Expressions. Please note that some packages in 'base' and 'opt' will depend on libpcre after recompiling. Example: base/grep Assuming that you've compiled a newer version of grep. `./configure` said: .. checking for pcre_exec in -lpcre... yes .. After `pkgrm libpcre` grep will say: $ grep string infile grep: error while loading shared libraries: libpcre.so.0: cannot open _ shared object file: No such file or directory 'grep' will not work without libpcre, please keep that in mind.