I sent this to gnats@ yesterday but got no response from it (is gnats
working?). Sorry for the possible duplicate.
>Synopsis: slattach over non-CLOCAL tty does not work
>Category: bin
>Environment:
System : OpenBSD 5.0
>Description:
slattach does not work on local lines or pseudo-terminals.
This problem report is based on:
http://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=3586
http://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=45759
>How-To-Repeat:
Use slattach on a serial line with a 3-wire cable, or:
# ifconfig sl0 up
# slattach /dev/ptyp0
slattach: TIOCSDTR: Inappropriate ioctl for device
>Fix:
I propose the patch below, so that slattach can be used successfully on
pseudo-terminal or in 3-wire mode (command is: slattach -l /dev/ptyp0).
diff -rup orig/src/sbin/slattach/slattach.c new/src/sbin/slattach/slattach.c
--- orig/src/sbin/slattach/slattach.c 2009-10-29 05:32:40.000000000 +0100
+++ new/src/sbin/slattach/slattach.c 2011-12-30 14:22:42.000000000 +0100
@@ -80,11 +80,14 @@ main(int argc, char *argv[])
sigset_t sigset;
int i;
- while ((ch = getopt(argc, argv, "hms:r:t:")) != -1) {
+ while ((ch = getopt(argc, argv, "hlms:r:t:")) != -1) {
switch (ch) {
case 'h':
cflag |= CRTSCTS;
break;
+ case 'l':
+ cflag |= CLOCAL;
+ break;
case 'm':
cflag &= ~HUPCL;
break;
@@ -123,7 +126,7 @@ main(int argc, char *argv[])
cfsetspeed(&tty, speed);
if (tcsetattr(fd, TCSADRAIN, &tty) < 0)
err(1, "tcsetattr");
- if (ioctl(fd, TIOCSDTR, 0) < 0)
+ if (ioctl(fd, TIOCSDTR, 0) < 0 && errno != ENOTTY)
err(1, "TIOCSDTR");
if (ioctl(fd, TIOCSETD, &slipdisc) < 0)
err(1, "TIOCSETD");
@@ -194,6 +197,6 @@ usage(void)
{
fprintf(stderr,
- "usage: slattach [-t ldisc] [-hm] [-s baudrate] ttyname\n");
+ "usage: slattach [-t ldisc] [-hlm] [-s baudrate] ttyname\n");
exit(1);
}
diff -rup orig/src/sbin/slattach/slattach.8 new/src/sbin/slattach/slattach.8
--- orig/src/sbin/slattach/slattach.8 2008-06-10 01:01:22.000000000 +0200
+++ new/src/sbin/slattach/slattach.8 2011-12-30 14:27:15.000000000 +0100
@@ -60,6 +60,10 @@ The following operands are supported by
.It Fl h
Turn on RTS/CTS flow control.
By default, no flow control is done.
+.It Fl l
+Turn on the CLOCAL flag, making it possible to run SLIP on a cable
+without modem control signals (e.g. DTR, DSR, DCD), or on a
+pseudo-terminal.
.It Fl m
Maintain modem control signals after closing the line.
Specifically, this disables HUPCL.
