When (e.g, after a system crash) a stale /var/lib/pgsql/data/postmaster.pid
file exists, the "postgresql start" init fails.  Also, and even worse, a
"postgresql stop" init also fails, after a very long delay, probably
because it tries to stop a non-existing process.

After removing the pid file, everything works fine.

Suggestion: maybe the init script can check whether the pid file is stale
or not, and remove it if it is a stale file, so that the standard
postgresql start/stop will work afterwards.