I broke the signal handler

[Lonni J Friedman]

Greetings,
I'm running xfce-4.10 on Fedora19 (Linux), using the official Fedora
RPMs.  Somehow, I've ended up with a situation where the signal
handler isn't working correctly.  This is evident from the following:
* in nearly any terminal window (xterm, aterm, urxvt, etc), hitting
'control-c' to abort the currently running command does nothing.
* attempts to detach from a screen session hangs, and I never get a
shell (bash) prompt back again.  The last thing I see is "[detached
from 8969.pts-11.hal]" (obviously with a different PID for different
screen sessions).

The only exception to all of the above is with xfce4-terminal.  Also,
I've confirmed that none of these problems reproduce over ssh, outside
of X (on a local virtual console), or with a newly created user.

So somehow I broke the signal handling, but I have no clue how. If I
attached strace to the wedged "screen -r" process, I see the following
repeating over and over again:
###########################
pause()                                 = ? ERESTARTNOHAND (To be
restarted if no handler)
--- SIGALRM {si_signo=SIGALRM, si_code=SI_KERNEL} ---
rt_sigreturn()                          = -1 EINTR (Interrupted system call)
alarm(0)                                = 0
kill(26681, SIG_0)                      = 0
rt_sigaction(SIGALRM, {0x7f8bbe6b7890, [], SA_RESTORER,
0x7f8bbd86aa60}, {0x7f8bbe6b7890, [], SA_RESTORER, 0x7f8bbd86aa60}, 8)
= 0
alarm(15)                               = 0
###########################


Anyone have any ideas how to debug or fix this?

thanks