I've been meaning to ask about this before.....

I never see any kerninfo line from SIGINFO on a serial console (at least
not on i386, alpha, or sparc).  The signal does get delivered, as you
can see from the following, but despite correct STTY settings there's no
line printed by the kernel.....

[tty00]<root@always> # dd if=/dev/zero of=/dev/null
^T126026+0 records in
126026+0 records out
64525312 bytes transferred in 0.824 secs (78307417 bytes/sec)
^T257776+0 records in
257775+0 records out
131980800 bytes transferred in 1.687 secs (78234024 bytes/sec)
^T489887+0 records in
489886+0 records out
250821632 bytes transferred in 3.205 secs (78259479 bytes/sec)
^C609162+0 records in
609161+0 records out
311890432 bytes transferred in 3.986 secs (78246470 bytes/sec)
[tty00]<root@always> # stty -a
speed 9600 baud; 24 rows; 80 columns;
lflags: icanon isig iexten echo echoe echok echoke -echonl echoctl
        -echoprt -altwerase -noflsh -tostop -flusho pendin -nokerninfo
        -extproc
iflags: -istrip icrnl -inlcr -igncr ixon -ixoff ixany imaxbel -ignbrk
        brkint -inpck -ignpar -parmrk
oflags: opost onlcr -ocrnl oxtabs onocr onlret
cflags: cread cs8 -parenb -parodd -hupcl clocal -cstopb -crtscts -mdmbuf
        -cdtrcts
cchars: discard = ^O; dsusp = ^Y; eof = ^D; eol = <undef>;
        eol2 = <undef>; erase = ^H; intr = ^C; kill = ^U; lnext = ^V;
        min = 1; quit = ^\; reprint = ^R; start = ^Q; status = ^T;
        stop = ^S; susp = ^Z; time = 0; werase = ^W;
[tty00]<root@always> # 


This is what I expect to see of course:

16:15 [1066] $ dd if=/dev/zero of=/dev/null
^Tload: 0.73  cmd: dd 25203 [running] 0.02u 0.61s 1% 144k
10654+0 records in
10653+0 records out
5454336 bytes transferred in 0.614 secs (8883283 bytes/sec)
^Tload: 0.73  cmd: dd 25203 [running] 0.06u 1.76s 6% 152k
31291+0 records in
31290+0 records out
16020480 bytes transferred in 1.826 secs (8773537 bytes/sec)
^?49666+0 records in
49665+0 records out
25428480 bytes transferred in 2.978 secs (8538777 bytes/sec)


(I have not tried a normal serial tty -- i.e. non-console.  I don't
think I have one hooked up anywhere to try at the moment....)


-- 
						Greg A. Woods

+1 416 218-0098                  VE3TCP            RoboHack <woods@robohack.ca>
Planix, Inc. <woods@planix.com>          Secrets of the Weird <woods@weird.com>