Top "Signals" questions

What does `kill -0 $pid` in a shell script do?

Basically, what signal does '0' represent, because here I see SIGNAL numbers starting from 1.

bash shell scripting signals kill

What is in Apache 2 a "caught SIGWINCH" error?

My server (ubuntu 8.04) LAMP running drupal 6, when there is high traffic, it stops serving pages. A restart of apache2 will …

ubuntu apache2 signals

Why can't Unix programs have signals with meaningful program defined names (rather than USR1, etc)?

Many Unix programs accept signals like USR1 and USR2. For example, to upgrade the executable for Nginx on the fly, …

unix signals

Debugging child process after fork (follow-fork-mode child configured)

I'm developing an application which the parent forks a child to handle certain tasks. I'm having an issue where I've …

c gdb signals fork

How to get cell service signal strength in Android?

I am trying to write a very simple Android application that checks the signal strength of the current cell. So …

android signals rssi

How to trap exit code in Bash script

There're many exit points in my bash code. I need to do some clean up work on exit, so I …

bash signals exit-code bash-trap

Calling pthread_cond_signal without locking mutex

I read somewhere that we should lock the mutex before calling pthread_cond_signal and unlock the mutex after calling …

c++ pthreads mutex signals condition-variable

How to stop 'uninterruptible' process on Linux?

I have a VirtualBox process hanging around which I tried to kill (KILL/ABORT) but without success. The parent pid …

linux signals sigabrt kill-process sigkill

Segmentation fault handling

I have an application which I use to catch any segmentation fault or ctrl-c. Using the below code, I am …

c linux signals signal-handling

PyQt4.QtCore.pyqtSignal object has no attribute 'connect'

I'm having issues with a custom signal in a class I made. Relevant code: self.parse_triggered = QtCore.pyqtSignal() def …

python pyqt signals pyqt4