Super User
Super User

Questions tagged [signal]

signal is a sequence of states in a communication system that encodes a message.

a signal is a physical quantity which varies with respect to time and space and carries information from source to destination.

140 questions
71
votes
4 answers

SIGTERM with a keyboard shortcut

I know that inside a terminal, Ctrl+C keyboard shortcut will send a SIGINT signal to the current foreground process. Is there a way to setup a keyboard shortcut for sending SIGTERM or even SIGKILL to the current process? I think it could save me…
julkiewicz
  • 813
24
votes
7 answers

Can a huge coiled LAN cable have some trouble for transmitting a signal?

Let's say I have a long (> 30m) LAN cable, that connect two (very close) devices. Could some of the unused wire, disposed as a huge coil, cause any issue ? I'm thinking about the special wire layout that would create a magnetic field (like in an…
tigrou
  • 943
21
votes
2 answers

Restart process on linux by its pidn number with kill command, how?

Well, I want to be able to restart processes on linux and so I looked into kill manpages for that. Apparently kill -l would list all the signals I could send to a process to do what I need, which are: 1) SIGHUP 2) SIGINT 3) SIGQUIT …
Ruben Marrero
  • 445
  • 1
  • 5
  • 12
15
votes
5 answers

How to block bluetooth signals?

We're developing software for bluetooth devices. We'd like to test the case when the device gets out of range, but don't want to carry the device to the other end of the office for each test. What is the easiest solution to block/shield bluetooth…
gabor
  • 261
11
votes
1 answer

How can I kill a parent process only?

I have the following processes. ParentProcess -- ChildProcess -- ChildProcess -- ChildProcess How can I kill the parent process only? I want the children processes not to be killed. If I try to kill the parent process, the children will get SIGHUP…
kcm1700
  • 133
11
votes
4 answers

Difference between shutdown ( power off ) and restart ( reboot )

What is Difference between shutdown (power off) and restart (reboot) ? What type of signals passing at time of reboot and poweroff, to where ? What is difference between these two signals ? At the time of reboot, Is the operating system go to…
Kumar
  • 453
11
votes
1 answer

What does IOT mean in regards to SIGIOT?

I've been looking around and I found that it was related to an abort call, Something to do with an IOT trap, but any resource I find seems to assume you already know what that is. Probably isn't important, but I saw it and was curious. I suppose…
DaggerOfMesogrecia
  • 253
8
votes
2 answers

Samsung monitor displays only "Check Signal Cable"

I suddenly got a 'Check Signal Cable' after turning on my monitor. It was working this morning I checked the vga cable. Inserted it to another monitor and it worked I have a Samsung S19A300B Radeon HD 4670 asus mobo and a pentium dual core e5300 i…
kapitanluffy
  • 373
7
votes
3 answers

Which Wifi Channel should I use?

Very confused. I'm using inSSiDer, WiFi Overview 360 and Wifi Analyzer apps to try to determine the best wifi channel to use. Assuming all channels are in use and there are about 20 different users in close proximity... Q1: Signal Strength If all…
Mike
  • 83
7
votes
3 answers

Can I automatically connect to the strongest wifi network under Windows 7?

I have a Windows 7 laptop, and 2 wifi connections. Windows 7 allows me to specify a strict preference list of networks in the "Manage Wireless Networks" under the Network and Sharing Center. However, of these 2, I'd always like to just connect to…
bacar
  • 172
6
votes
1 answer

How an unprivileged user could kill a process she didn't start?

I stumbled upon something very surprising which I cannot understand on a Red Hat EL 5.6 box : the user hri (which is in the group dba) is able to kill processes owned by user oracle (which is also in group dba). Is anybody able to explain what could…
Mathieu MD
  • 91
6
votes
1 answer

Fedora Linux: Way to use stty (or equivalent) to bind key to raise SIGUSR1 for application?

I'm using FC 14, but this is probably a fairly generic Linux question. I want to be able to bind a key in the Linux terminal driver that will cause a signal other than SIGINT or SIGQUIT to be raised for the running application. I don't want to…
RoUS
  • 203
6
votes
2 answers

How to disable ^C from being echoed on Linux on Ctrl-C

When I press Ctrl-C in any pseudoterminal (xterm, gnome-terminal, rxvt, text console and SSH) in Karmic Koala, the string ^C gets echoed to the terminal in Ubuntu Karmic Koala. This hasn't happened in Ubuntu Jaunty Jackalope. I'd like to get rid of…
pts
  • 7,648
4
votes
1 answer

Noise coming from HDD or CPU in headphones

I hear weird high sounds coming from my headphones. It is obvious that it has something to do with HDD or CPU because it's highlight sounds are heard when I it is writing data on HDD but also many other things like mouse moving etc. Here is a…
Milano
  • 275
4
votes
1 answer

GNU screen quitting -- sigterm to running process

I want to quit screen session. For this, I use screen -S session_name -X quit. This works well, but not like I would. The program running in screen has a handler for SIGTERM, and I really need this handler to execute, so that it can perform proper…
Xaqq
  • 161
1
2 3
…
9 10