Here's an example of what's going on with external binaries.
- catdoc spits output to stdout so $result contains output
- pdftotext spits output to filename.txt so $result is empty
This means that if the external binary that you are using outputs to stdout, then there is no need to add the switch statement given in the previous post, as $result contains the necessary info for indexing the document.
However, if the external binary does not output to stdout but rather outputs to a file, and the document is not indexed, then check the file extension in the temp directory, modifying the switch statement as necessary.
EDIT: external binary process modified in version 1.6.4.