Note: This tip applies primarily to UNIX platforms (fortunately or unfortunately). The code was run on a Sun Solaris server (SunOS 5.8).

How many times have you wondered what programs installed on your machine will handle content of a given type? There’s an easy utility that does this called apropos.

Suppose you want to find the programs/libraries related to .jpeg. Give the following command:

apache 21> apropos jpegcjpeg           cjpeg (1)       - compress an image file to a JPEG filedjpeg           djpeg (1)       - decompress a JPEG file to an image filejpegtran        jpegtran (1)    - lossless transcoding of JPEG filesrdjpgcom        rdjpgcom (1)    - display text comments from a JPEG filewrjpgcom        wrjpgcom (1)    - insert text comments into a JPEG file

As you can see, this returned five programs related to .jpeg. Of course, the output will differ depending on your system.