NAME¶

entr—run arbitrary commands when files change

SYNOPSIS¶

DESCRIPTION¶

A list of files provided on standard input, and theutilityis executed using the supplied arguments if any of them change.entrwaits for the child process to finish before responding to subsequent filesystem events.A TTY is also opened before entering the watch loop in order to supportinteractive utilities.

The arguments are as follows:

-a

Respond to all events which occur while theutilityis running.Without this option,entrconsolidates events in order to avoid looping.This option has no effect in conjunction with the-rflag.

-c

Clear the screen before invoking theutilityspecified on the command line.Specify twice to erase the scrollback buffer.

-d

Track the directories of regular files provided as input and exit if a new fileis added.This option also enables directories to be specified explicitly.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 modeentrdoes not attempt to read from the TTY or change its properties.

-p

Postpone the first execution of theutilityuntil a file is modified.

-r

Reload a persistent child process.As with the standard mode of operation, autilitywhich terminates is not executed again until a file system or keyboard event isprocessed.SIGTERMis used to terminate theutilitybefore it is restarted.A process group is created to prevent shell scripts from masking signals.entrwaits for theutilityto 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 theSHELLenvironment variable.

-x

Format custom exit status messages using a persistentawk(1)process.The path to the status script is defined by the environment variableENTR_STATUS_SCRIPT.If the status script does not exist,entrwill create an example.Shell commands and file redirection is not permitted by default, but may beenabled by specifying-xtwice.

-z

Exit after theutilitycompletes.When combined with-rtheutilitywill be restarted again only in response to commands or file systemevents.

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-soption is used, the name of the first file to trigger an event can be read from$0.

COMMANDS¶

entrlistens for keyboard input and responds to the following commands:

⟨space⟩

Execute the utility immediately.If the-roption is set this will terminate and restart the child process as if a filechange event had occurred.

q

Quit; equivalent pressing⟨control-C⟩.

ENVIRONMENT¶

ENTR_STATUS_SCRIPT

The path to the exit status script enabled by the-xoption.By default$HOME/.entr/status.awkis evaluated.

PAGER

Set to/bin/catby defaultto prevent interactive utilities from waiting for keyboard input if output doesnot fit on the screen.

SHELL

Specify the shell to use with the-sflag.The default is/bin/sh.

EV_TRACE

Print file system event messages.

EXIT STATUS¶

If the-zflag is set and theutilityis successfully executed, the status of the child process is returned.If the child process was terminated by a signal, the exit status is the signalnumber plus 128.

entrnormally returns one of the following values:

EXAMPLES¶

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

Launch and auto-reload a node.js server:

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

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

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