One application of this could be writing to a SQLite database. If you wrap your writes in a shell script controlled by a lock directory, you are guaranteed to

One application of this could be writing to a SQLite database. If you wrap your writes in a shell script controlled by a lock directory, you are guaranteed to never receive SQLITE_BUSY. #!/bin/sh until mkdir /var/tmp/mylock do sleep 1; done trap 'rmdir /var/tmp/mylock' ABRT EXIT FPE HUP INT QUIT SEGV TERM sqlite3 mydatabase.db 'INSERT INTO MYTABLE VALUES (1,2,3);' Since the mkdir() is atomic, the SQLite busy handler is now irrelevant with this approach. On Linux, there is also an flock utility, but it tends to need subshells which are not as efficient. EDIT: This does reduce the write performance to one of these executions per second. Simple inserts like this can hit a few dozen per second otherwise, as I have heard.