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From: Pablo Funes <pablo@cs.brandeis.edu>
Message-Id: <199904122119.RAA31982@mancha.cs.brandeis.edu>
Subject: nonblocking lock?
To: pgsql-interfaces@postgresql.org
Date: Mon, 12 Apr 1999 17:19:37 -0400 (EDT)
Content-Type: text

Is it possible to do a nonblocking lock? That is, 
I want several clients to execute,

    begin
    if table A is locked
    then
        go around doing stuff on other tables
    else
        lock A and do stuff on A
    endif

the problem is, if I use normal lock, then 
after one client has locked and is doing stuff on A
the other one will block and thus it won't be able
to go around doing stuff on other tables. Is it
possible to do a nonblocking lock that will just
fail if the table is locked already? 

Thank you 

Pablo Funes
Brandeis University
pablo@cs.brandeis.edu