Question

I’m using Ubuntu. I have two bash script files. Both will run in parallel. Now I want to continuously monitor on another file that it is running or not.

So any way to find that the file is currently executing or not ?

Answer 1

Numerous possibilities, it is a question of creativity…

Some suggestions:

• periodically poll the process list and filter it by name or process id
• start the script with control sockets, as long as the sockets are open the script runs
• use the usual locking strategy in file system.
• have the script do a lifebeat on a regular base, then watch that lifebeat.
• start the script in a series of commands, the moment the script exists the next command will be executed by the calling shell. That one could be a notification script or something.
• have the script do some wiggling on your desktop and watch it yourself.
• start it using nohup and watch the log file.
• implement a deamon inside the script and connect periodically.
• open a file from within the script and watch the file system using the fuser system call.
• periodically write a token into a file by the monitoring script and have the monitored script remove that token, like a baton.
• call the script using a blocking call. The script executes as long as that blocking call does not return.
• create a singleton strategy on process level and simply try starting it periodically.
• make the monitoring script act as a monitor deamon the executing script connects to. If the connection is terminated the scipt obviously has stopped executing.
• …

Sorry, this starts getting boring…