Using the PHP -W flag in a batch file

I'm trying to remove all white space and code comments from my .php files by using the -W flag available from the PHP CLI. I'm using a batch file to recursively loop through each php file in my project. The batch command looks like:

FOR /F "tokens=*" %%G IN ('DIR /B /A-D /S *.php') DO "%php-exe-path%/php.exe" -w %%G > %%G 

This just produces blank .php files (using the '>' redirector), however using the appending redirector ('>>') works fine. I'm not sure i开发者_高级运维f this is an issue with PHP locking the files or some problem with my batch command.

Can anyone help?

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Generally: Don't ever pipe the output of a command that works with a file into the file again. Instead pipe to a temporary file, delete the old one and rename the temporary one to the old name. Kinda like the following:

FOR /F "tokens=*" %%G IN ('DIR /B /A-D /S *.php') DO (
    "%php-exe-path%/php.exe" -w %%G > %%G.temp
    del %%G
    ren %%G.temp %%G
)

Side note: Please don't use for /f over the output of dir as that can introduce some subtle but nasty errors. Instead use the proper way of iterating over files which is just plain for, and recursively with the /r switch:

FOR /R %%G IN (*.php) DO (
    "%php-exe-path%/php.exe" -w %%G > %%G.temp
    del %%G
    ren %%G.temp %%G
)