I think that this "getc/putc works with single-character abort" is not really as big an advantage as it seems. getc/putc are simply a standard 1-character buffer on FILE *'s provided by posix. It would be about 10 lines to write a similar system that can buffer up entire lines, and that will work equally as well with single-character aborts or "abort" as a text command. The advantages of a readable text "abort" outweigh the simuler code in POSIX systems for single character aborts in my opinion. Although I admit, now we're getting into opinions rather than facts, so it is harder to really argue either side of this.
One thing I haven't heard discussed, does anybody really dislike having an optional "abort" command? Or is everybody OK with adding a section to the spec that says "If you support aborting commands, this is the way to do it"?
On Tue, 2002-10-29 at 03:00, Markus Enzenberger wrote: the single character solution leaves the possibility open for a simple implementation on POSIX systems avoiding the need for a thread. You could use select, getc and putc to poll at certain times during your lengthy command and do a blocking read when waiting for the next real command. Putc allows you to put back only one character. (It does not work if there is still something in stdio's buffer, but this is no problem, since interrupting won't be used in batch mode anyway).