shell - Alert when file content changes -

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• monitor directory content change 2 answers

i want write shell script checks logic files placed @ /var/www/html/ and, if user makes change in files, sends alert administrator informing them "user x has made change in f file." not have experience in writing shell scripts, , not know how start. highly appreciated.

this answered in superuser: https://superuser.com/questions/181517/how-to-execute-a-command-whenever-a-file-changes

basically use inotifywait

simple, using inotifywait:

while inotifywait -e close_write myfile.py; ./myfile.py; done 

this has big limitation: if program replaces myfile.py different file, rather writing existing myfile, inotifywait die. editors work way.

to overcome limitation, use inotifywait on directory:

 while true;   change=$(inotifywait -e close_write,moved_to,create .)   change=${change#./ * }   if [ "$change" = "myfile.py" ]; ./myfile.py; fi done 

the asker has put script online that, can called this:

while sleep_until_modified.sh derivation.tex ; latexmk -pdf derivation.tex ; done