determining if DCE device is ready

[Peter da Silva]

In article <130199 at uunet.UU.NET> rbj at uunet.UU.NET (Root Boy Jim) writes:
> Or you can get trickier.
> Fork a child for each device you want to open. The child
> will block on the open. When the carrier comes on, the open
> will succeed. Have the child exit, which will then send a
> death of child signal to the parent. The parent will then
> open the device (in non blocking mode, just in case).

If the device on the other side (say, a modem) pays attention to DTR
this will mess up:

	child issues open		DTR raises
					Modem raises CD
	open completes
	child exits
	file descriptor closes		DTR drops
					Modem drops carrier

Oops.
-- 
Peter da Silva.  `-_-'  peter at ferranti.com
+1 713 274 5180.  'U`  "Have you hugged your wolf today?"