How to automatically restart the process after stopping the recording in the log file?

Question

linux

There is a FFMPEG process that writes to the log during its execution. After the source disappears, the process hangs and is not deleted. The log accordingly ceases to be written. Help me write a script that would track changes in the log and restart the process when recording stops.
Ps. there is another option to monitor an open port
via telnet or monitor the output of rtmpdump

Answer 1

#!/bin/bash
log=имя_лог_файла
while((`date +%s` - `date +%s -r $log` > 20)); do # если текущее время и время изменения лога больше 20 секунд
   # перезапускаем ffmpeg
   sleep 5 # проверяем каждые 5 секунд
done