About "lock file postmaster.pid" Error , cannot setup postmaster

[Ying Lu <ying_lu@cs.concordia.ca>]

Hello all,

I met a  problem about cannot start postmaster.

The situation I met is that I was running postmaster, but because of the 
server closed all my konsole. As a result, I did not shutdown postmaster 
successfully. Next time, when I tried to run
postmaster -D /usr/local/postgresql/data, I got the following error:

FATAL:  lock file "/usr/local/postgresql/data/postmaster.pid" already exists

Thanks in advance,
Emi