inotifywait

uses Linux's inotify API to efficiently watch files and directories for changes

TLDR

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

$ inotifywait [path/to/file]

Continuously watch a file for events

$ inotifywait -m [path/to/file]

Watch a directory recursively for events

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

Watch a directory excluding files matching regex

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

Watch with a timeout of 30 seconds

$ inotifywait -m -t 30 [path/to/file]

Watch only for specific events (modify)

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

Watch quietly (no status messages)

$ inotifywait -q [path/to/file]

Run a command when a file is accessed

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

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 writingThis is commonly used in scripts to rebuild projects, sync files, or trigger deployments when source files change.

PARAMETERS

-m, --monitor

Keep running, don't exit after first event

-r, --recursive

Watch directories recursively

-e, --event EVENT

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

-t, --timeout SECONDS

Exit after timeout with no events

-q, --quiet

Suppress informational messages

--exclude PATTERN

Exclude files matching regex pattern

--format FMT

Custom output format

-c, --csv

Output in CSV format

INSTALL

sudo apt install inotify-tools

sudo dnf install inotify-tools

sudo pacman -S inotify-tools

sudo apk add inotify-tools

sudo zypper install inotify-tools

brew install inotify-tools

nix profile install nixpkgs#inotify-tools

CAVEATS

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.

HISTORY

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.