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v. 1. To delete something, usually superfluous, or to abort an operation.

"All that nonsense has been flushed."

2. [UNIX/C] To force buffered I/O to disk, as with an 'fflush(3)' call. This is *not* an abort or deletion as in sense 1, but a demand for early completion!

3. To leave at the end of a day's work (as opposed to leaving for a meal).

"I'm going to flush now."

"Time to flush."

4. To exclude someone from an activity, or to ignore a person.

'Flush' was standard ITS terminology for aborting an output operation; one spoke of the text that would have been printed, but was not, as having been flushed. It is speculated that this term arose from a vivid image of flushing unwanted characters by hosing down the internal output buffer, washing the characters away before they can be printed. The UNIX/C usage, on the other hand, was propagated by the 'fflush(3)' call in C's standard I/O library (though it is reported to have been in use among BLISS programmers at DEC and on Honeywell and IBM machines as far back as 1965). UNIX/C hackers find the ITS usage confusing, and vice versa.