Re: [patch] DTR/DSR hardware handshake support for 2.0/2.2/2.4

From: Theodore Ts'o (
Date: Wed Aug 02 2000 - 13:52:10 EST

   Date: Wed, 2 Aug 2000 11:47:28 EDT
   From: Frank da Cruz <>

   Yes, I'll second this. I get requests for DTR/DSR (and DTR/CD) hardware
   flow control in Kermit all the time for this kind of reason. The equipment
   involved is not "legacy" (my least favorite word -- in common parlance it
   means "not Microsoft") at all, just weird.

Actually, I usually use "legacy" in connection to Microsoft. (As in,
legacy web servers such as Microsoft IIS :-)

   There are standard APIs in SVR4 for all sorts of hardware flow control,
   specified in <termiox.h> (or <sys/termiox.h>):

   struct termiox * arg;

The problem with this sort of API is that it involves effectively
extending the termios structure, and there are a number of other chnages
that need to be made, including using a numeric input/output baud rate
fields. I consider this a 2.5 issue.

Using some new flags in c_cflags is the way to go, if we decide to go
this way. But it does mean chewing up a bunch of extra bits, and I
really do wonder how many people *really* need this. Maybe I'll set up
a survey on to determine whether or not there's
enough people to want this kind of feature bloat..... in any case, I'm
not terribly inclined to consider this before 2.4, especially since
Linus finally seems to be serious about the code freeze.

                                        - Ted

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
Please read the FAQ at

This archive was generated by hypermail 2b29 : Mon Aug 07 2000 - 21:00:09 EST