Podcast #128: We chat with Kent C Dodds about why he loves React and discuss what life was like in the dark days before Git. Listen now.

Questions tagged [signal]

Questions about signals, a kind of interprocess communication.

Filter by
Sorted by
Tagged with
0
votes
0answers
22 views

Signal emitted by “Force Quit” option when killing a non-responsive GUI task

I have a GTK application written in C that sometimes becomes unresponsive. It spawns a child process that is not killed when the "Force Quit" option is selected to kill the GUI, as seen below: I ...
0
votes
0answers
24 views

How to define default application permanently?

This is a follow up on this question : https://stackoverflow.com/questions/58180711/launching-jupyter-notebook-from-terminal-starts-signal-desktop-messenger-as-well/58225284#58225284 After I changed ...
1
vote
0answers
32 views

half signal strength from wireless rtl8188ce lubuntu

I get super slow speeds (half the signal strength I get on windows) and an unstable connection. I ran this script and this is the info I get on Lubuntu 19.04 Kernel 5.0.0-29-generic. 02:00.0 Network ...
0
votes
0answers
20 views

How to move one process from SWAP to RAM?

As far as I can see, there is a design error in how my processes are moved between SWAP and RAM: If RAM gets full, some are moved to SWAP. So far so good. But if RAM gets freed, they are not moved ...
1
vote
1answer
36 views

What does it mean when ^\ doesn't work, but kill -9 does?

Recently, I've had a third-party program hang in a weird way. It stops taking input or output, and ^C and ^\ do nothing. kill -9 and killing the parent process do end it. What state could the process ...
1
vote
1answer
67 views

SIGQUIT breaks the pipe

Linux ping utility can produce some statistics on receiving SIGQUIT without terminating. It looks like this: PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data. 64 bytes from 8.8.8.8: icmp_seq=1 ttl=45 time=...
0
votes
0answers
29 views

FIRM ware blocking signal

I use the internet signal from a common router in my building. The system has worked well for several months but now I can still get the internet on my laptop but no longer on my desktop (both are PCs)...
0
votes
0answers
82 views

Synchronize Signal contacts on signal-desktop in Ubuntu 18 from Signal on Ubuntu Touch (Fairphone2)

I installed the Signal app on my Fairphone2 running Ubuntu Touch. Contacts were correctly imported from contacts list to the app. I installed the Signal desktop client for Ubuntu 18 on my computer ...
0
votes
0answers
19 views

Difference in Wifi connection %'s?

This is something I've wondered about for a long time...Ubuntu 16.04 using Cinnamon. On a tower computer. In the action bar I have the Wifi icon. It shows that I'm currently connected to the local ...
0
votes
0answers
140 views

rtl8812au weak wifi signal in linux, fine in windows

I could use some help with this, I'm not a programmer, I know a few of the basics. But this problem is really frustrating me.
1
vote
0answers
42 views

Which version of Signal Desktop is legit? [duplicate]

I saw both of these in the apt sources. Since this is a secure communications app, what is the correct source to use for Ubuntu? Searching for Signal, I see: And lower: With these details: Before ...
0
votes
0answers
15 views

Signal interrupt for UTC clock

How to get signal interrupt from UTC clock at specific time? For example I want to get signal interrupt at 1AM everyday. How can I do this on X86 machine? Thanks, Shailav
0
votes
0answers
49 views

Execute a particular piece of code just before shutdown

I have written a c++ program, which contains an infinite loop. I am going to run this program from terminal. Now what I want my program to do is- when I shutdown Ubuntu, a particular function must be ...
1
vote
0answers
134 views

Multiple repository errors when I try any APT command after trying to install signal [duplicate]

I am currently using 18.04. I wanted to install signal for desktop and I got this code from the site to install on Debian: curl -s https://updates.signal.org/desktop/apt/keys.asc | sudo apt-key add ...
0
votes
1answer
197 views

Send multiple kill signals to a process

Say I run a .sh process. And now I open a new terminal tab and I want to send signals to it, for that, I just use kill: kill -*signal number* *pid* right? But I want to send 13 signals at the same ...
0
votes
1answer
382 views

Signal messenger app not starting up

Over the past 2 weeks (after installing Ubuntu 18.04 from scratch) I have had problems on and off with the Signal messenger app. It sometimes doesn't start up at all. Uninstalling and reinstalling ...
2
votes
2answers
379 views

Sending SIGSTOP or SIGCONT signals graphically (similar to xkill)

Question Do you know any tool/script to send SIGSTOP (to pause a process) or SIGCONT (to resume it) to a process by clicking on a graphical window generated by the process? Some context There is ...
0
votes
1answer
453 views

Week wireless signal in Linux mint [closed]

After installing Linux Mint 18.3 "Sylvia" - Cinnamon (64-bit) on my HP laptop, I realize that the WiFi signal is a way too weak and the modem and the router is near my laptop. Model: HP Probook 4540s
3
votes
0answers
1k views

How can I get yarn to use the right version of Node?

I am new to Node, JavaScript etc. and want to try messing with the code of Signal. For this I need a specific version of Node. I did this (on Ubuntu 16.04) using the following procedure: wget https://...
1
vote
0answers
291 views

Upstart service killed by TERM signal, how to track that

I have upstart script as description "My API API" author "me@localhost" env MY_API_PYTHON_HOME=/opt/services start on runlevel [2345] stop on runlevel [!2345] script mkfifo /tmp/my-api-log-fifo ...
1
vote
1answer
2k views

Ubuntu 16.04, hdmi monitor: no signal in login screen

My main monitor is connected over HDMI and my second one over DVI. Both get a signal when the PC starts up, but the moment I get to the login screen the HDMI one goes dark, though it doesn't seem to ...
0
votes
1answer
175 views

Chromium Signal App crashing in Xubuntu

When I try to launch Signal through the launcher on Linux with the following /usr/bin/chromium-browser --profile-directory=Default --app-id=bikioccmkafdpakkkcpdbppfkghcmihk It crashes, nothing ...
2
votes
0answers
123 views

Ubuntu 16.04LTS Four monitor display issue

I've been browsing the forum trying to find a solution to my specific problem but can't find anything specific. My graphics card is the Radeon R9 380 Sapphire Nitro. I have three DVI displays, one of ...
0
votes
1answer
116 views

Why sigset includes unadded SIGINT? [closed]

Wrote simple program to learn writing POSIX style signal handling. #include <signal.h> #include <errno.h> #include <stdio.h> #include <stdlib.h> static void sig_int(int); ...
2
votes
1answer
261 views

Disable “System program problem detected” for segfaults in my own programs

I don't mind being notified about system programs that SEGV -- I would actually like to report those cases, so this is not a duplicate of Getting “System program problem detected” pops up regularly ...
0
votes
1answer
2k views

Weak WiFi signal in Ubuntu on HP G240 G5 [duplicate]

I had purchased new HP 240 G5 laptop. Wifi is working good with windows but in ubuntu 16 wifi signal comes very weak. Below are laptop wifi details, *-network description: Wireless interface ...
1
vote
0answers
71 views

Ubuntu 16.04 immediately terminates all running programs on restart or shutdown?

When I choose restart or shutdown in Ubuntu 16.04, it immediately terminates all running applications. I'm not prompted to save open documents or anything like that - and I've lost work several times ...
0
votes
2answers
289 views

How to pass SIGALRM to a program which finishes execution in milliseconds?

I have a C program which computes the first n prime numbers if n is passed as an argument. $ ./prime 5 2 3 5 7 11 The logic of the program allows me to enter into a desired function if I can give ...
1
vote
1answer
2k views

No SIGTERM before SIGKILL/shutdown with systemd on Ubuntu 16.04

I ran across this problem while I tried to answer a question on Stackoverflow. On shutdown, Ubuntu 12.04 sends SIGTERM to all processes and waits at most 10 seconds before killing them with SIGKILL (...
2
votes
1answer
604 views

After upgrade to 16.04, wifi signal strength jumps from perfect to zero and back

I upgraded from 14.04 LTS to 16.04 LTS on HP Z230. Internet connection worked perfectly under 14.04 LTS. There were no hardware changes. The computer connects to the router by a wireless usb device (...
0
votes
1answer
577 views

xvfb-run hangs on trap/wait in Elastic Bamboo's Ubuntu 15.04 AMI on AWS

I'm trying to run some headless robot/Selenium tests via Elastic Bamboo using Xvfb, on Ubuntu 15.04 in AWS EC2. It works if I run Xvfb manually and then run the test... export display=:99 Xvfb :99 -...
0
votes
2answers
383 views

Ubuntu 14.04 wireless unstable and the signal is weak

I installed Ubuntu 14.04 LTS alongside Win8.1 and the wireless was unstable. I updated windows network drivers then it went better but the signal is still very weak and also sometimes network switches ...
1
vote
2answers
1k views

Wifi apparently connected, but webpages won't load

I'm running the latest Ubuntu 14.04.3, and my issue today is that my Wifi connection sometimes becomes really slow, and eventually disconnects. I tried googling around to see if I can get any good ...
0
votes
2answers
724 views

Difference between C programs and shell scripts receiving signals from fuser

I have written the shell script below for a lab in my college. It must look at a log file being upgraded frequently from another process and create a number of copies passed at invokation. Here is the ...
0
votes
1answer
1k views

index out of range? [closed]

# load parameters file yml = yaml.load(open(sys.argv[1])) # imports for pkg, functions in yml['imports'].iteritems(): stri = 'from ' + pkg + ' import ' + ','.join(functions) exec(stri) ...
1
vote
0answers
370 views

Why does sudo prevent catching SIGTSTP (Ctrl+Z)?

This program is written to catch SIGTSTP (Ctrl+Z) and bypass its normal effect, printing a message and returning to its normal operation instead of allowing its process to be suspended: #include<...
1
vote
0answers
69 views

The UBUNTU Graphics Catch 22

Trying to use a Live DVD to run Ubuntu 14.04.1, I get the "Monitor signal out of range" error. I hit ctrl-alt-F1 to bring up the command line. I do sudo nano /etc/default/grub and remove # from ...
-1
votes
2answers
1k views

12.04 wifi signal very weak

Ii am new people in Ubuntu I am using 12.04 version , but my wifi signal very weak My router beside me only , my signal also only 50% ... Anybody know how to fix it?i have try to research solution, ...
1
vote
1answer
2k views

emit signal with custom type objects array parameter from c++ and receive in qml

I would like to emit a signal from a Qt C++ class which includes a parameter that is an array of custom objects (inherited from QObject) and receive the parameter in its qml slot, but i'm afraid it is ...
0
votes
1answer
59 views

sigfillset is not setting signal bits

I am having this strange problem! My code is very simple. #include<stdio.h> #include<unistd.h> #include<signal.h> #include<stdlib.h> main(...
1
vote
1answer
1k views

What do these Terminal Signals mean?

When I start to use a command to terminate an ongoing process, I can include a signal. What is the difference between the signal 9 and the signal 15?
0
votes
1answer
236 views

Ubuntu 13.10, not recognizing 2nd monitor

Just installed ubuntu for the first time and my monitor isn't showing up on the display settings. I am on a laptop with nivdia graphics if that helps. I believe I have bumblebee installed. Other ...
2
votes
0answers
343 views

Core only dumped upon receiving SIGQUIT

Learning about signals, I found out that calling the <stdlib.h> functionabort(void); in a C program, which roughly equals to raising a SIGABRT signal, doesn't create a core file on my Ubuntu 13....
2
votes
0answers
1k views

Unix Signal handling in Qt Embedded Linux [closed]

I have an application for the USB interface in Qt (Embedded Linux). When a pen-drive is inserted, the kernel sends a signal for that and I want to recognize that signal and I want my Qt application ...
0
votes
1answer
886 views

TP Link TL-WN7200ND Signal Strength

I have external Wireless Adapter TP Link TL-WN7200ND I'm currently using it on Windows its giving me 4/5 signal bars When I used same Adapter in Ubuntu 13.04 it gives 2/4 bars. I'm using Live USB for ...
1
vote
0answers
404 views

no internet connection, but have signal in wifi

I cannot access yahoo.com, google etc in my browser, but I have signal in my WiFi, how can I access the internet again? Please can you tell me how to configure and solve my problem, Thanks
3
votes
1answer
2k views

Bad WiFi reception on Asus Zenbook (Works great with Windows 7)

My WiFi reception on my Asus Zenbook (model ux31) is very weak compared to when I boot my Windows 7. I use both from the same location, and the reception on other devices (ex: my iPhone) is great. I'm ...
3
votes
3answers
1k views

How can I tell how long for Watchdog to wait to stop all processes?

I have a server which is monitored by Watchdog, and experiences reboots occasionally due to faulty network hardware I am unable to replace at the moment. As I read, Watchdog sends a SIGTERM to all ...
1
vote
1answer
467 views

Keep VGA signal sending when using VGA switchbox

I am trying to mimic the VGA projector setup I had on Arch Linux. I have three laptops connected through a VGA switchbox to an external projector. When I was using ArchLinux I used xrandr to start ...
1
vote
1answer
2k views

Weak wifi signal on Lenovo g series

I've just installed Ubuntu 12.10 on my Lenovo laptop and the wifi signal reception changed completely. I had Windows installed on it first and it had no problem connecting to my home network from my ...