umodem

[lauren%rand-unix at vortex.UUCP]

If you're trying to run UMODEM on 4.2, you'll have to alter the
alarm signal handling.  I wrote the original code assuming standard
V7/4.1 signal interruption handling (i.e. the read call returns with
a -1 if interrupted).  Good ol' 4.2 doesn't work that way (it normally
continues the read) so you'll have to use longjmp's or some other 
mechanism to compensate...

--Lauren--