---
name: "entr"
section: "1"
platform: "linux"
package: "entr"
version: "5.9-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/entr"
---

# entr(1)

run arbitrary commands when files change

## NAME

**entr** – run arbitrary commands when files change

## SYNOPSIS

**entr** \[**-acdnprsxz**\] *utility* \[*argument* */\_* *...*\]

## DESCRIPTION

A list of files provided on standard input, and the *utility* is executed using the supplied arguments if any of them change. **entr** waits for the child process to finish before responding to subsequent file system events. A TTY is also opened before entering the watch loop in order to support interactive utilities.

The arguments are as follows:

- **-a**

  Respond to all events which occur while the *utility* is running. Without this option, **entr** consolidates events in order to avoid looping. This option has no effect in conjunction with the **-r** flag.

- **-c**

  Clear the screen before invoking the *utility* specified on the command line. Specify twice to erase the scrollback buffer.

- **-d**

  Track the parent directory of regular files provided as input. If specified twice, all new entries to a directory are recognized, otherwise files with names beginning with ‘.’ are ignored.

- **-n**

  Run in non-interactive mode. In this mode **entr** does not attempt to read from the TTY or change its properties.

- **-p**

  Postpone the first execution of the *utility* until a file is modified.

- **-r**

  Reload a persistent child process. As with the standard mode of operation, a *utility* which terminates is not executed again until a file system or keyboard event is processed. A process group is created to prevent shell scripts from masking signals. **entr** waits for the *utility* to exit to ensure that resources such as sockets have been closed. Control of the TTY is not transferred to the child process.

- **-s**

  Evaluate the first argument using the interpreter specified by the SHELL environment variable.

- **-x**

  Format custom exit status messages using a persistent [awk(1)](/awk/1.md) process. The path to the status script is defined by the environment variable ENTR\_STATUS\_SCRIPT. If the status script does not exist, **entr** will create an example. Shell commands and file redirection is not permitted by default, but may be enabled by specifying **-x** twice.

- **-z**

  Exit after the *utility* completes. When combined with **-r** the *utility* will be restarted again only in response to commands or file system events.

The first argument named */\_* is replaced with the absolute path of the first file to trigger an event. The first file under watch is used as the default. If the **-s** option is used, the name of the first file to trigger an event can be read from *$0*.

## COMMANDS

**entr** listens for keyboard input and responds to the following commands:

- ⟨**space**⟩

  Execute the utility immediately. If the **-****r** option is set this will terminate and restart the child process as if a file change event had occurred.

- **q**

  Quit; equivalent pressing ⟨**control-C**⟩.

## ENVIRONMENT

- ENTR\_STATUS\_SCRIPT

  The path to the exit status script enabled by the **-x** option. By default *$HOME/.entr/status.awk* is evaluated.

- ENTR\_RESTART\_SIGNAL

  Signal used to terminate the *utility*. Supported signal names are HUP, INT, QUIT, TERM, USR1 and USR2. The default is SIGTERM.

- EV\_TRACE

  Print file system event messages.

- PAGER

  Set to */bin/cat* by default to prevent interactive utilities from waiting for keyboard input if output does not fit on the screen.

- SHELL

  Specify the shell to use with the **-s** flag. The default is */bin/sh*.

## EXIT STATUS

If the **-z** flag is set and the *utility* is successfully executed, the status of the child process is returned. If the child process was terminated by a signal, the exit status is the signal number plus 128.

**entr** normally returns one of the following values:

- 0

  Normal termination after receiving SIGINT

- 1

  No regular files were provided as input or an error occurred

- 2

  Files were added or removed from a directory

## EXAMPLES

Rebuild a project if source files change, limiting output to the first 20 lines:

```
$ find src/ | entr -s 'make | head -n 20'
```

Launch and auto-reload a node.js server:

```
$ ls *.js | entr -r node app.js
```

Clear the screen and run a query after the SQL script is updated:

```
$ echo my.sql | entr -cp psql -f /_
```

Rebuild project if a source file is modified or added to the src/ directory:

```
$ while sleep 0.1; do ls -d src src/*.rb | entr make; done
```

Auto-reload a web server, or terminate if the server exits

```
$ ls * | entr -rz ./httpd
```

## AUTHORS

Eric Radman ⟨*ericshane@eradman.com*⟩