NAME
lckdo - run a program with a lock held
SYNOPSIS
lckdo [options] {lockfile} {program} [arguments]
DESCRIPTION
lckdo runs a program with a lock held, in order to prevent multiple
processes from running in parallel. Use just like nice or nohup.
Now that util-linux contains a similar command named flock, lckdo is
deprecated, and will be removed from some future version of moreutils.
OPTIONS
-w If the lock is already held by another process, wait for it to
complete instead of failing immediately.
-W {sec}
The same as -w but wait not more than sec seconds.
-e Execute the program directly without forking and waiting (keeps
an extra file descriptor open).
-E {nnn}
Set the file descriptor number to keep open when exec()ing
(implies -e).
-n Do not create the lock file if it does not exist.
-q Produce no output if lock is already held.
-s Lock in shared (read) mode.
-x Lock in exclusive (write) mode (default).
-t Test for lock existence.
EXIT STATUS
If the lock was successfully acquired, the return value is that of the
program invoked by lckdo. If the lock couldn't be acquired, EX_TEMPFAIL
is returned. If there was a problem opening/creating or locking the
lock file, EX_CANTCREAT or EX_OSERR will be returned.
AUTHOR
Michael Tokarev
2007-08-15 lckdo(1)