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Table of Contents
Directory - Run a Command Upon Files or Directories Changes
Use either inotifywait or iwatch.
Using inotifywait
Install inotify-tools
sudo apt install inotify-tools
Test inotifywait
In a shell enter:
while true; do res=`inotifywait -r thedirtowatch/ --format %f`; echo "RESULT=$res"; done
returns:
Setting up watches. Beware: since -r was given, this may take a while! Watches established.
NOTE: The %f** refers to the filename in the event. See http://manpages.ubuntu.com/manpages/focal/man1/inotifywait.1.html for options. </WRAP> —- In a 2nd shell, go to that directory being watched. <code bash> touch test1 </code> NOTE: Back on the 1st shell this should show you output: <code bash> RESULT=test1 </code> —-
NOTE: An additional -e option can be added to the inotifywait to only listen for certain events.
For example:
while true; do res=`inotifywait -e create, open, close, modify, moved_to, moved_from -r thedirtowatch/ --format '%e %f'` ; echo "RESULT=$res\n"; done
The --format option is changed to include showing %e which is the actual event. Obviously change as needed.
See http://manpages.ubuntu.com/manpages/focal/man1/inotifywait.1.html for options.
—- ===== More ===== <code bash> inotifywait -m -e modify,create -r /yourpath && \ chmod 644 file; && \ chown blah:blah file; </code>
NOTE:
- -m, –monitor: Instead of exiting after receiving a single event, execute indefinitely. The default behavior is to exit after the first event occurs.
- -r, –recursive: Watch all sub-directories of any directories passed as arguments. Watches will be set up recursively to an unlimited depth.
- Symbolic links are not traversed. Newly created sub-directories will also be watched.
—- ===== Using a BASH Script ===== <file bash after-change.sh> #!/bin/bash # # Monitor the input directory and if any change occurs run the provided command: # # Usage: # after-change.sh /tmp ls -al %f if [ $# -lt 3 ]; then echo “Usage: $0 dir cmd ” exit 1 fi which inotifywait 2>&1 >/dev/null if [ “$?” == “1” ]; then echo “ERROR: inotifywait not installed.” exit 1 fi dir=$1 shift cmd=$1 shift options=$* inotifywait -q -r -m $dir $options eval $cmd </file> —- ===== References ===== http://manpages.ubuntu.com/manpages/focal/man1/inotifywait.1.html