We make Kerio MailServer, a somewhat popular commercial Linux mail
server. I have a customer who was crashing with no core dump. So, I
ran our product through strace.

The "error log" of our product, when run through strace, started
filling up with this: 

services.cpp: Select failed in services acceptor loop: (514) Unknown
error 514

When I look at the strace, I see that a call to socket() is receiving
ERESTARTNOHAND. From Googling, my understanding is that userspace
(even libc) should never see this signal. I will attach the relevant
strace.

I don't see this problem when I'm not running it through strace.

Versions:
uname -a: Linux ashe.fitnessquest.com 2.4.21-9.0.3.ELsmp #1 SMP Tue
Apr 20 19:49:13 EDT 2004 i686 i686 i386 GNU/Linux

strace-4.5.1-1.EL.1
glibc-2.3.2-95.6

Steps to Reproduce:
1. Install Kerio MailServer 5.7.9
2. Run it through strace with strace -ff -t
3. After about a day, the strace will be full of:

08:04:36 select(45, [44], NULL, NULL, {1, 0}) = 0 (Timeout)
08:04:37 select(45, [44], NULL, NULL, {1, 0}) = ? ERESTARTNOHAND (To
be restarted)
08:04:37 --- SIGSTOP (Stopped (signal)) @ 0 (0) ---
08:04:37 select(45, [44], NULL, NULL, {0, 100000}) = 0 (Timeout)
08:04:38 select(45, [44], NULL, NULL, {1, 0}) = ? ERESTARTNOHAND (To
be restarted)
08:04:38 --- SIGSTOP (Stopped (signal)) @ 0 (0) ---