lckdo man page

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

Info

2007-08-15 moreutils moreutils