GNU Portability Library

Gnulib is intended to be the canonical source for most of the important
"portability" and/or common files for GNU projects. These are filesintended to be
shared at the source level; Gnulib is not a typical library meant to be installed
and linked against. Thus, unlike most projects, Gnulib does not normally generate
a source tarball distribution; instead, developers grab modules directly from the
source repository.