setlock(8)                                             setlock(8)


NAME
       setlock - runs another program with a file locked.

SYNOPSIS
       setlock [ -nNxX ] fn child

DESCRIPTION
       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

       o      closed  by  all the processes that have descriptors
              for it or

       o      explicitly unlocked.

OPTIONS
       -n     No delay. If fn is locked by another process,  set-
              lock gives up.

       -N     (Default.)  Delay.  If fn is locked by another pro-
              cess, setlock waits until it can obtain a new lock.

       -x     If fn cannot be opened (or created) or locked, set-
              lock exits zero.

       -X     (Default.) If fn cannot be opened (or  created)  or
              locked,  setlock  prints an error message and exits
              nonzero.

SEE ALSO
       supervise(8), svc(8), svok(8),  svstat(8),  svscanboot(8),
       svscan(8),  readproctitle(8), fghack(8), pgrphack(8), mul-
       tilog(8),   tai64n(8),    tai64nlocal(8),    setuidgid(8),
       envuidgid(8), envdir(8), softlimit(8)

       http://cr.yp.to/daemontools.html












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