Provided by: moreutils_0.50_amd64
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)