In article <1992Oct5.141626.15853@prime.mdata.fi> kennu@mits.mdata.fi (Kenneth Falck) writes:
quoted text
>I would like to try to program a little terminal for linux that
>would just copy keyboard input to the modem-tty, and everything
>from the modem to the console.

I already have a program that does this - I didn't think people would
find it too useful, but I'll put it somewhere for FTP if you want.

quoted text
>Under MSDOS this is easy, because
>you can eat up all the CPU time checking for keyboard input and
>modem input in a tight wait loop, but how should one go on doing
>this under a multiuser/multitasking system?

The select() system call, to cut a long story short.  It is given a
time-out and a list of file handles to check, and it blocks until
either the time-out expires or one of the file handles becomes ready
to be read, written, or shows an exceptional condition.

quoted text
>Is there any way to make "interrupts" or call-backs to a user-
>specified function

Not that I know of.  I'd be interested to know of a way though.
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