inotifywait

Watch a specific file for events, exiting after the first one

$ inotifywait [path/to/file]

$ inotifywait -m [path/to/file]

$ inotifywait -m -r [path/to/directory]

$ inotifywait -m -r --exclude "[regex]" [path/to/directory]

$ inotifywait -m -t 30 [path/to/file]

$ inotifywait -e modify [path/to/file]

$ inotifywait -q [path/to/file]

$ inotifywait -e access [path/to/file] && [command]

inotifywait [options] file...

inotifywait uses Linux's inotify API to efficiently watch files and directories for changes. It blocks until a filesystem event occurs, making it ideal for triggering actions on file changes.
Available events include:
- access - File read
- modify - File written
- create - File/directory created
- delete - File/directory deleted
- move - File moved
- attrib - Metadata changed
- close_write - File closed after writing
This is commonly used in scripts to rebuild projects, sync files, or trigger deployments when source files change.

-m, --monitor

Keep running, don't exit after first event

Watch directories recursively

Watch for specific events (access, modify, create, delete, etc.)

Exit after timeout with no events

Suppress informational messages

Exclude files matching regex pattern

Custom output format

Output in CSV format

Linux-only (uses inotify kernel subsystem). There are limits on the number of watches (configurable via /proc/sys/fs/inotify/maxuserwatches). Recursive watching creates a watch per directory. Not suitable for very large directory trees.

inotifywait is part of inotify-tools, created to provide user-space access to Linux's inotify API, which was introduced in kernel 2.6.13 (2005). It replaced the older dnotify mechanism.

inotifywatch(1), entr(1), fswatch(1), fatrace(1)