port not working!!

Haller jhh at ihlpl.UUCP
Fri Mar 14 01:23:17 AEST 1986


I used to have problems with my 7300 port hanging on opens, when I discovered
a generic feature of setting CLOCAL.  I would open /dev/tty000 with
O_NDELAY, then set CLOCAL, and expect to be able to write immediately.
I discovered that CLOCAL has NO EFFECT during the ioctl.  Opening the
/dev/tty000 again, while the fd with CLOCAL set remains open, allows
writes to occur.  If you are trying to write before there is carrier
on the line, this may be the problem.

John Haller



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