# Watchexec CLI
A simple standalone tool that watches a path and runs a command whenever it detects modifications.
Example use cases:
* Automatically run unit tests
* Run linters/syntax checkers
## Features
* Simple invocation and use
* Runs on Linux, Mac, Windows, and more
* Monitors current directory and all subdirectories for changes
* Uses efficient event polling mechanism (on Linux, Mac, Windows)
* Coalesces multiple filesystem events into one, for editors that use swap/backup files during saving
* By default, uses `.gitignore` and `.ignore` to determine which files to ignore notifications for
* Support for watching files with a specific extension
* Support for filtering/ignoring events based on [glob patterns](https://docs.rs/globset/*/globset/#syntax)
* Launches the command in a new process group (can be disabled with `--no-process-group`)
* Sets the following environment variables in the process:
* If a single file changed (depending on the event type):
* `$WATCHEXEC_CREATED_PATH`, the path of the file that was created
* `$WATCHEXEC_REMOVED_PATH`, the path of the file that was removed
* `$WATCHEXEC_RENAMED_PATH`, the path of the file that was renamed
* `$WATCHEXEC_WRITTEN_PATH`, the path of the file that was modified
* `$WATCHEXEC_META_CHANGED_PATH`, the path of the file whose metadata changed
* If multiple files changed:
* `$WATCHEXEC_COMMON_PATH`, the longest common path of all of the files that triggered a change
* This can be disabled or limited with `--no-environment` and `--no-meta`
* Optionally clears screen between executions
* Optionally restarts the command with every modification (good for servers)
* Does not require a language runtime
## Anti-Features
* Not tied to any particular language or ecosystem
* Does not require a cryptic command line involving `xargs`
## Usage Examples
Watch all JavaScript, CSS and HTML files in the current directory and all subdirectories for changes, running `make` when a change is detected:
$ watchexec --exts js,css,html make
Call `make test` when any file changes in this directory/subdirectory, except for everything below `target`:
$ watchexec -i target make test
Call `ls -la` when any file changes in this directory/subdirectory:
$ watchexec -- ls -la
Call/restart `python server.py` when any Python file in the current directory (and all subdirectories) changes:
$ watchexec -e py -r python server.py
Call/restart `my_server` when any file in the current directory (and all subdirectories) changes, sending `SIGKILL` to stop the command:
$ watchexec -r -s SIGKILL my_server
Send a SIGHUP to the command upon changes (Note: using `-n` here we're executing `my_server` directly, instead of wrapping it in a shell:
$ watchexec -n -s SIGHUP my_server
Run `make` when any file changes, using the `.gitignore` file in the current directory to filter:
$ watchexec make
Run `make` when any file in `lib` or `src` changes:
$ watchexec -w lib -w src make
Run `bundle install` when the `Gemfile` changes:
$ watchexec -w Gemfile bundle install
Run two commands:
$ watchexec 'date; make'
If you come from `entr`, note that the watchexec command is run in a shell by default. You can use `-n` or `--shell=none` to not do that:
$ watchexec -n -- echo ';' lorem ipsum
On Windows, you may prefer to use Powershell:
$ watchexec --shell=powershell -- test-connection localhost
## Installation
### First-party
#### Pre-built
Use the download section on **[the website](https://watchexec.github.io/downloads/)** to obtain the
package appropriate for your platform and architecture, extract it, and place it in your `PATH`.
There are also Debian/Ubuntu (DEB) and Fedora/RedHat (RPM) packages.
Checksums and signatures are available.
#### Cargo (from source)
Requires Rust 1.43 or later.
$ cargo install watchexec-cli
#### [Binstall](https://github.com/ryankurte/cargo-binstall)
$ cargo binstall watchexec-cli
### Third-party
These are provided by third parties, caveat emptor!
#### macOS
- Homebrew: `$ brew install watchexec`
- Nix/NixOS: `$ nix-env -iA nixpkgs.watchexec`
- Webi: `$ curl -sS https://webinstall.dev/watchexec | bash`
#### Linux
- ArchLinux: `$ pacman -S watchexec`
- Nix/NixOS: `$ nix-env -iA nixpkgs.watchexec`
- Webi: `$ curl -sS https://webinstall.dev/watchexec | bash`
#### Windows
- Scoop: `#> scoop install watchexec`
- Chocolatey: `#> choco install watchexec`
- Webi: `#> curl.exe -A MS https://webinstall.dev/watchexec | powershell`
## Shell completions
Currently available shell completions:
- zsh: `completions/zsh` should be installed to `/usr/share/zsh/site-functions/_watchexec`