wr
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watch files and run a command when they change
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NAME
----
`wr` -- watch files and run a command when they change
SYNOPSIS
--------
wr [-cvV] command [file ...]
DESCRIPTION
-----------
`wr` will watch the set of files and directories specified on the
command line, and run the specified command when any of the files
changes. For each file operand which is a directory, all the files
in the directory (recursively) will be watched.
If no files are specified, it's as if you passed "." as the file parameter.
The following options are available:
`-c --chime minutes`
> Write a diagnostic message after `minutes` have elapsed since last running
> a command, to remind you `wr` is running. The default is 5 minutes.
> Use the value 0 to disable the chime.
`-v --verbose`
> Generate additional diagnostic information.
`--exec`
> Use exec instead of spawn to run the command.
`-p --poll seconds`
> Use a polling file watcher. The default is to use a non-polling file watcher.
> The non-polling file watcher
> may have a relatively small maximum number of files it can watch (200),
> but the polling file watcher has no maximum.
> The polling file
> watcher may incur delays between a file changing and the command running,
> compared to the non-polling file watcher.
`-V`
> Display the version number and exit.
`-? -h`
> Display help.
EXAMPLES
--------
The following is how to run make when any file in the current directory
changes:
wr make
More likely you can whittle the list of source files checked a bit. The
following will run make any file in the `src`, `doc` or `test` directories
changes:
wr make src doc test
To run a command with arguments, quote the command you want to run. The
following will run the command "`echo a file changed`" when any file in the
current directory changes:
wr "echo a file changed"
DIAGNOSTICS
-----------
wr will not normally exit. Use ctrl-c or equivalent to kill the process
from the command-line.
Diagnostic information from `wr` will be written to stderr.
ENVIRONMENT
-----------
If the current directory has a `.wr` file in it, that file is assumed
to have the contents of a `wr` invocation in it. Options, option/value
pairs, the command to run, and each file to be watched should be
specified on separate lines.
The file may contain blank lines or lines starting with the `#` character,
which are considered comments.
The stdout and stderr from the command being run are passed directory to
`wr`'s stdout and stderr. stdin for the command will not be available
for the command.
The command will be run in either spawn or exec mode, as determined by
command-line options. Here are the differences:
exec:
* the command will not be parsed, as will be run as given
* should handle i/o redirection shell operators
* stdout and stderr output will be buffered until the command is complete
spawn:
* the command will be parsed into space separated tokens, probably
misinterpreting any quotes you have in your command
* will not handle i/o redirection shell operators
* stdout and stderr output will not be buffered
HISTORY
-------
`wr` is a port of Patrick Mueller's [run-when-changed.py](https://gist.github.com/240922)
script to node.
**2012-05-03: version 1.2.0**
* [commit d684efb7](https://github.com/pmuellr/wr/commit/d684efb7182bd866c875be2bb459a692a5661599) - replaced charm w/colors
**2012-05-03: version 1.2.0**
* [issue 8](https://github.com/pmuellr/wr/issues/8) - add elapsed time to success and failure messages
* fixed bug where wr fired off it's command when the access time changed on a file
**2012-01-11: version 1.1.0**
* [issue 1](https://github.com/pmuellr/wr/issues/1) - chime should print the time
* [issue 2](https://github.com/pmuellr/wr/issues/2) - chime should default to 5 minutes
* [issue 3](https://github.com/pmuellr/wr/issues/3) - .wr file parser should accept option/value on a single line
* [issue 5](https://github.com/pmuellr/wr/issues/5) - provide option to use stat-based polling
* [issue 6](https://github.com/pmuellr/wr/issues/6) - use spawn instead of exec to run commands
* [issue 7](https://github.com/pmuellr/wr/issues/7) - colorize stdout and stderr
**2012-01-10: version 1.0.1**
* fixed some stupid bugs
**2012-01-09: version 1.0.0**
* initial release