Question

I need to update a website that is moving to a new host. I would like to add the following line to each file, only once, after the first occurrence of <?php:

define('FRAMEWORK_LOCATION', '/home/someUser/framework.php');

I have tried several variations of this Perl oneliner:

$ find . -name '*' -print0 | xargs -0 perl -pi -e 's|<?php|<?php\rdefine('\''FRAMEWORK_LOCATION'\'', '/home/someUser/framework.php');'

However, as can be seen it would affect all lines. I am not particularly concerned about the case of additional code after the initial <?php though if a solution does take that into account then that would be good for me to learn from as well.

Answer 1

You can directly use sed, without invoking perl:

$ find . -name '*' -type f -print0 | xargs -0 sed -e '0,/<?php/s||&\ndefine("FRAMEWORK_LOCATION","/home/someUser/framework.php")|'

The relevant bit is:

sed -e '0,/<?php/s||&\nNEW_TEXT|'

where you are specifying:

1. the range 0,/<?php: from the first line to the first occurrence of <?php
2. the substitution s||&\nNEW_TEXT|: where you substitute the previous match <?php with itself followed by a new line with some new text.

Note that I added the switch -type f to find for filtering out directories.