Phil is a portability library for flavors of Unix. It includes a C library, some programs & code for portable shell programming, some tips for portable makefiles, & this documentation, which describes installing Phil, writing programs to make use of Phil, & general portability tips.
Appropriate readers include
I assume the reader agrees that portability is a valuable feature in software, at least among flavors of Unix. If the reader doesn't see any value in portable software, Phil is probably not of any interest to that reader. I do not attempt to convince the reader of the importance of portability.
This document is written in LATEX.