14 Feb
2002
14 Feb
'02
1:25 a.m.
Hi!
From: David W Talmage
<talmage(a)cmf.nrl.navy.mil>
Would someone please advise me about fifos and sockets in 2.11BSD?
Ok ;)
Don't use fifos - they don't exist (as you probably have found
out by now :))
I'm having
trouble porting screen 3.9.9, the multiplexing terminal emulator, to 2.11BSD
fifos and sockets are just the tip of the iceberg when it comes
to 'screen'. Eons ago (when screen was a fairly new program) I made
an attempt at porting it and ran into the address space problems - seems
that screen wants to use lots of large buffers, has lots of strings
(all the help, etc) and so on.
because of them. I'm running Mr. Schultz's
2.11BSD with all patches up to
#442 on Mr. Brandt's p11 emulator version 2.9. FWIW, I have INET in my kernel
but I've ifconfig-ed only lo0.
Thanks for the "ownership" label but I think of it more as being
a 'steward' and coordinator than anything else
p11 2.9? Wow, I've an old patched/hacked 2.5 because I can't seem
to find p11's home now - begemot.org doesn't mention anything about
"p11".
The fifo test portion of the configure script fails
when writing to the fifo.
The write() returns -1 and sets errno == 79, "Inappropriate file type or
Right, FIFOs don't exist. One of those things I never could find
the need or time for ;)
format". This happens when I run the test as
root, as I must in order to use
mknod() to create the fifo. See fifotest.c, below.
If 2.11's mknod can create fifos that is _news_ to me. I don't recall
seeing (or adding) that capability.
screen can use sockets instead of fifos. That portion
of the configure script
fails as well. It fails in that it does not return from the select() on the
socket until the alarm goes off. See socketstest.c, below.
Now that is very strange. Unix domain sockets do work (syslogd
uses them for example) so I'm at a loss to explain why the test
program isn't working.
One thing I did do is after running "./a.out&" was do an immediate
'ps'. That should see 2 a.out processes due to the 'fork()' call.
I only say one. This tells me that the alarm was started (obviously
since alarm(5) is the first thing executed) but the child process
raced thru and exited before the parent got to the select() call.
With the child exited the select() will block until interrupted by
the alarm() call.
Steven Schultz
sms(a)2bsd.com