Initial import of the lockf utility. It executes an arbitrary command

while holding an exclusive lock on a file.

1 files changed, 95 insertions, 0 deletions

diff --git a/usr.bin/lockf/lockf.1 b/usr.bin/lockf/lockf.1
new file mode 100644
index 0000000..6b78644
--- /dev/null
+++ b/usr.bin/lockf/lockf.1
@@ -0,0 +1,95 @@
+.\"
+.\" Copyright (C) 1997 John D. Polstra.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY JOHN D. POLSTRA AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL JOHN D. POLSTRA OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" $Id$
+.\"
+.Dd January 8, 1997
+.Os FreeBSD
+.Dt LOCKF 1
+.Sh NAME
+.Nm lockf
+.Nd execute a command while holding a file lock
+.Sh SYNOPSIS
+.Nm
+.Op Fl s
+.Op Fl t Ar seconds
+.Ar file
+.Ar command
+.Op Ar arguments
+.Sh DESCRIPTION
+The
+.Nm
+utility acquires an exclusive lock on a
+.Ar file ,
+creating it if necessary.
+While holding the lock, it executes a
+.Ar command
+with optional
+.Ar arguments .
+After the
+.Ar command
+completes,
+.Nm
+releases the lock and removes the
+.Ar file .
+BSD-style locking is used, as described in
+.Xr flock 2 ;
+the mere existence of the 
+.Ar file
+is not considered to constitute a lock.
+.Pp
+The following options are supported:
+.Bl -tag -width Fl
+.It Fl s
+Causes
+.Nm
+to operate silently.
+Failure to acquire the lock is indicated only in the exit status.
+.It Fl t Ar seconds
+Specifies a timeout for waiting for the lock.  By default,
+.Nm
+waits indefinitely to acquire the lock.
+If a timeout is specified with this option,
+.Nm
+will wait at most the given number of
+.Ar seconds
+before giving up.  A timeout of 0 may be given, in which case
+.Nm
+will fail unless it can acquire the lock immediately.
+.El
+.Pp
+In no event will
+.Nm
+break a lock that is held by another process.
+.Sh DIAGNOSTICS
+If
+.Nm
+is unable to acquire the lock, it returns an exit status of 1.
+Otherwise, it returns the exit status produced by
+.Ar command .
+.Sh SEE ALSO
+.Xr flock 2 .
+.Sh AUTHORS
+John Polstra,
+.Aq jdp@polstra.com .