We are running postgresql 7.2 on Red Hat Linux 7.3, and occasionally
we run into the problem where the postmaster.pid is still hanging
around from an improper shutdown (i.e. computer crash due to power
problems).

I know that I can go in and delete the old postmaster.pid, and it will
start up fine...but I have a couple of questions:

1. Why doesn't postgres see that an old pid is present during
startup, and remove it (or at least provide a flag that can be set to
force the removal).

2. Is it ok to add to the startup script code that will remove the
pid if one is present?

3. Is it left hanging around for a reason?

Thanks,
Dan