tunafish
n. In hackish lore, refers to the mutated punchline of
an age-old joke to be found at the bottom of the manual pages of
`tunefs(8)' in the original BSD 4.2 distribution. The
joke was removed in later releases once commercial sites started
using 4.2. Tunefs relates to the `tuning' of file-system
parameters for optimum performance, and at the bottom of a few
pages of wizardly inscriptions was a `BUGS' section consisting of
the line "You can tune a file system, but you can't tunafish".
Variants of this can be seen in other BSD versions, though it has
been excised from some versions by humorless management
droids. The [nt]roff source for SunOS 4.1.1 contains a
comment apparently designed to prevent this: "Take this out and a
Unix Demon will dog your steps from now until the `time_t''s
wrap around."