string replace in a large file with php

php string replace readfile
Brian picture Brian · Jan 29, 2010 · Viewed 15.6k times · Source

I am trying to do a string replace for entire file in PHP. My file is over 100MB so I have to go line by line and can not use file_get_contents(). Is there a good solution to this?

Answer

Dominic Barnes picture Dominic Barnes · Jan 29, 2010

If you aren't required to use PHP, I would highly recommend performing stuff like this from the command line. It's by far the best tool for the job, and much easier to use.

In any case, the sed (Stream Editor) command is what you are looking for:

sed s/search/replace oldfilename > newfilename

If you need case-insensitivity:

sed s/search/replace/i oldfilename > newfilename

If you need this to perform dynamically within PHP, you can use passthru():

$output = passthru("sed s/$search/$replace $oldfilename > $newfilename");

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