How can i output the children of a process as a number in Bash

Question

I want to output to a text.log the count of the childrens of a process searching them by name not with PID. For example i want to count the processes of firefox by name and output them in the text file as a number "6" .

Answer 1

By PID using the ps command:

ps --ppid PID_OF_PROC | wc -l

If you need it recursively, meaning childs of childs included then use:

ps x --ppid PID_OF_PROC | wc -l