This package (built using the facilities of ) provides a macro \catchfilebetweentags acts like the original \catchfile but only extracts a portion of the file instead of the complete file. The extracted portion can be delimited by strings or by docstrip tags:
%<*tag> .... %</tag>
(comments in the caught region may be included or dropped).

The author is Florent Chervet. The package is Copyright © 2010 Florent Chervet.