'\"macro stdmacro
.\"
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.TH PMLOCK 1 "PCP" "Performance Co-Pilot"
.SH NAME
\f3pmlock\f1 \- simple file-based mutex
.SH SYNOPSIS
.B $PCP_BINADM_DIR/pmlock
[\fB\-i\fR \fIident\fR]
[\fB\-v\fR]
.I file
.SH DESCRIPTION
.B pmlock
attempts to acquire an exclusive lock by creating a zero-sized
.I file
with a mode of 0.
.PP
The
.I \-i
option changes the behaviour to write
.I ident
into
.IR file ,
followed by a newline and the file mode is 0444.
.I ident
is an arbitrary string, but by convention it is the
process id of the locker followed by the name or identification
of the locker command or script.
.PP
The exit status is 0 for success, 1 for failure.
.PP
To release the lock, remove
.I file
with
.BR rm (1)
or
.BR unlink (2).
.PP
In the event of a failure, the
.B \-v
option produces an explanatory message on
.IR stderr .
.SH SEE ALSO
.BR rm (1)
and
.BR unlink (2).