setlock 1 user commands djbwares setlock runs another program with a file locked. setlock -n -N -x -X fn child fn is a single argument. child consists of one or more arguments. setlock opens fn for writing (creating it if it does not exist), obtains an exclusive lock on it, and runs child. Normally the lock disappears when child exits. Here's the complete story: child is given a descriptor for a locked ofile pointing to the disk file named fn. The lock disappears when this ofile is either closed by all the processes that have descriptors for it or explicitly unlocked. -n No delay. If fn is locked by another process, setlock gives up. -N (Default.) Delay. If fn is locked by another process, setlock waits until it can obtain a new lock. -x If fn cannot be opened (or created) or locked, setlock exits zero. -X (Default.) If fn cannot be opened (or created) or locked, setlock prints an error message and exits nonzero. supervise1 svc1 svok1 svstat1 svscanboot1 svscan1 readproctitle1 fghack1 pgrphack1 multilog1 tai64n1 tai64nlocal1 setuidgid1 envuidgid1 envdir1 softlimit1 Original code and documentation by Daniel J. Bernstein. Converted to manual pages and updated by Gerrit Pape in 2000, 2001, and 2002. Converted to DocBook XML by Jonathan de Boyne Pollard.