.TH setlock 8
.SH NAME
setlock \- runs another program with a file locked.
.SH SYNOPSIS
.B setlock
[
.B \-nNxX
]
.I fn
.I child
.SH DESCRIPTION
.I fn
is a single argument.
.I child
consists of one or more arguments. 

.B setlock
opens
.I fn
for writing (creating it if it does not exist), obtains an exclusive lock on
it, and runs
.IR child .

Normally the lock disappears when
.I child
exits. 

Here's the complete story:
.I child
is given a descriptor for a locked ofile pointing to the disk file named
.IR fn .
The lock disappears when this ofile is 
.IP o
closed by all the processes that have descriptors for it or 
.IP o
explicitly unlocked. 
.SH OPTIONS
.TP
.B \-n
No delay. If
.I fn
is locked by another process,
.B setlock
gives up. 
.TP
.B \-N
(Default.) Delay. If
.I fn
is locked by another process,
.B setlock
waits until it can obtain a new lock. 
.TP
.B \-x
If
.I fn
cannot be opened (or created) or locked,
.B setlock
exits zero. 
.TP
.B \-X
(Default.) If
.I fn
cannot be opened (or created) or locked,
.B setlock
prints an error message and exits nonzero.
.SH SEE ALSO
supervise(8),
svc(8),
svok(8),
svstat(8),
svscanboot(8),
svscan(8),
readproctitle(8),
fghack(8),  
pgrphack(8),
multilog(8),
tai64n(8),
tai64nlocal(8),
setuidgid(8),
envuidgid(8),
envdir(8),
softlimit(8)

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