Monitor directory listing for changes?

Question

On a unix system, how do I monitor (like how \'tail\' works) a directory for changes made to files - either new ones created, or size changes, etc.

Looking for a com

Answer 1

Most unix variants have an API for this, but it's not standardized. On Linux, there is inotify. On the command line, you can use inotifywait. Usage example:

inotifywait -m /path/to/dir | while read -r dir event name; do
  case $event in
    OPEN) echo "The file $name was created or opened (not necessarily for writing)";;
    WRITE) echo "The file $name was written to";;
    DELETE) echo "The file $name was deleted ";;
  esac
done

Inotify event types are often not exactly what you're trying to notice (e.g. OPEN is very wide), so don't feel bad if you end up making your own file checks.