postmaster -S will not print an error if pid file exists

Started by Peter Eisentrautalmost 25 years ago3 messages
#1Peter Eisentraut
peter_e@gmx.net

If a second postmaster is started on a data directory and the second one
uses the -S option it will not print a message but simply exit and not
start a background process. The exit status is 0.

This seems to have gotten lost in the changes postmaster.c rev. 1.195,
global lock file changes by tgl.

--
Peter Eisentraut peter_e@gmx.net http://yi.org/peter-e/

#2Tom Lane
tgl@sss.pgh.pa.us
In reply to: Peter Eisentraut (#1)
Re: postmaster -S will not print an error if pid file exists

Peter Eisentraut <peter_e@gmx.net> writes:

If a second postmaster is started on a data directory and the second one
uses the -S option it will not print a message but simply exit and not
start a background process. The exit status is 0.

Since the whole point of -S is to throw away stdout/stderr, I hardly
see how you can complain about the fact that the error message went
to /dev/null. I agree that zero exit status is not good, however;
will see if I can fix that.

regards, tom lane

#3Tom Lane
tgl@sss.pgh.pa.us
In reply to: Peter Eisentraut (#1)
Re: postmaster -S will not print an error if pid file exists

Peter Eisentraut <peter_e@gmx.net> writes:

If a second postmaster is started on a data directory and the second one
uses the -S option it will not print a message but simply exit and not
start a background process. The exit status is 0.

On closer inspection, it's clear that the postmaster *does* exit with
status 1 after failing to lock the lockfile. However, since it's
already forked and detached from the terminal, you can't see the status
1; the parent process exited with status 0. Postponing the fork till
after we grab the lockfile will not do, because then the lockfile will
contain the wrong postmaster PID.

I have stated before that I consider -S evil. Don't complain too hard
about its behavior, or I'll fix it by ripping it out, lock stock and
barrel ;-)

regards, tom lane