How to find and kill a process in one line using bash and regex?

A common way to find and kill processes in one line using bash (with a regex-like pattern) is to use pkill (or pgrep + kill). For example:

pkill -f 'pattern'

• -f tells pkill to match against the entire command line (not just the process name).
• 'pattern' can be a regular expression that matches the process(es) you want to kill.

If you prefer a pipeline approach with grep and awk, you can do something like:

ps aux | grep -E 'your_regex_pattern' | awk '{print $2}' | xargs kill -9

Explanation:

1. ps aux: Lists all running processes.
2. grep -E 'your_regex_pattern': Filters the process list by your regex.
3. awk '{print $2}': Prints the PID (process ID) from the second column of the ps output.
4. xargs kill -9: Sends a SIGKILL (-9) to each PID from the pipeline.

Note: Use -9 with caution; it force-kills processes and doesn’t allow them to clean up. If a gentler approach is acceptable, consider using just kill (default signal is TERM) or pkill -TERM -f 'pattern'.

Examples

1. Using pkill -f:

   # Kills any process whose command line matches 'java.*MyServer'
   pkill -f 'java.*MyServer'

2. Using ps + grep + awk + xargs:

   # Kills processes that match 'my_script.*arg'
   ps aux | grep -E 'my_script.*arg' | awk '{print $2}' | xargs kill -9

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