A good way to see how various p4 functions are used is to look at the example programs included in the distribution. The p4/monitors directory contains shared-memory examples written in C that use monitors, including one instrumented with ALOG. The p4/messages subdirectory contains message-passing examples written in C. The programs in p4/messages_f are Fortran message-passing examples, and the p4/contrib and p4/contrib_f directories contain a number of miscellaneous examples contributed by users. In each directory there is a README that describes the individual examples.
Getting Started,Specifying Processes in the Procgroup File,Installing p4,Top