dyx

Oh, after carefully check the man page of flock(1) in Linux, it supports timeout. So the last value of this program disappears. Please ignore my ignorance and disturbance. I wish I could delete the post but there is no way to do it.

I implement this program since flock(1) in Linux doesn't support timeout of pending.

I've never used BSD. After reading the link provided by you, I think my program becomes no value, if there is a Linux version of lockf(1). Sad.

You are right in this situation.

The scene for this program is that I don't know all the tasks.

Namely, tasks are generated in real time.

1. I posted some task to the queue and continue my work, then the work make me post another work. e. g. in a shell script

2. For server application to queue tasks

1. I want to run commands in background, but sequentially 2. Used in a server application for queued long-time task