Questions tagged [process]
A process is an instance of a computer program that is being executed.
2,275
questions
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Loading executable bbject files and creating private area
I was reading a textbook on virtual memory and it says:
Any Linux program can invoke the loader by calling the execve function which does:
1-Delete the existing area structs in the user portion of the ...
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0answers
14 views
duplicated permission control for a virtual page?
I'm reading a textbook which talks about virtual memory. And it says there is a R/W Read-only or read/write access permission control bit in a page table entry, so the R/W bit determines whether the ...
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1answer
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the structure of the virtual memory of a Linux process
I'm reading a textbook which shows virtual memory as:
Linux also maps a set of contiguousvirtual pages (equal in size to the total amount of DRAM in the system) to the corresponding set of contiguous ...
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4answers
62 views
How to avoid killing a wrong process when using PID number for killing?
I'm starting a long-running background process inside a Bash script. I'm saving the PID number after sending the process to background and since that process has that PID number as long as it runs, ...
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1answer
31 views
how come a virual address is only 48 bits rather than 64 bits?
I was reading a book which talks about virtual memory:
Intel Core i7 supports a 48-bit (256 TB) virtual address space and a 52-bit (4 PB) physical address space
below is my question
Q1-since we ...
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2answers
41 views
Why can't some processes run in the background in Linux terminal while others can, despite all being able to print to the terminal?
I use Linux terminal in Ubuntu.
When I write seq 100 1 | less & to run it it in the background, it just stops.
I used other ways to run it on background too, like using bg [jobnr] but it just ...
0
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0answers
7 views
Kill background process bash not working from current shell [duplicate]
I'm doing trap to kill subprocesses of script and it's working perfectly:
myscript.sh
trap "kill 0" EXIT
./someProcessA &
./someProcessB &
the problem that I don't understand why ...
0
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0answers
2 views
Default specific processes to higher priorities with lutris or otherwise?
I'm running Manjaro XFCE (20.1 at the time of writing) and I would like to make lutris, or some other third-party program, automatically launch all games with a default niceness value of -6 or ...
0
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1answer
55 views
How to get PID from within bash shell script
I have the following code that submits several subjobs withing a docker container:
#!/bin/bash
for file in "all files of a given type"; do
docker exec -itd "docker container"...
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0answers
21 views
How do I find the PID of the active window, where the application is a flatpak?
I can find the information easily for regular applications with something like:
xdotool getactivewindow getwindowname
xdotool getactivewindow getwindowpid
VLC media player
28448
However with the ...
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0answers
13 views
Why does Message+ randomly pop up on my processes on Kali?
I watch my network using "top" and I notice message+ keeps randomly popping up for about 1-2 seconds then disappears. What is this and why is this happening? I can't find anything on it.
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1answer
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Call only async-signal-safe functions in signal handlers?
I'm new to signal and signal handler and I was reading a book which says
Call only async-signal-safe functions in your handlers. A function that is async-signal-safe, or simply safe, has the property ...
0
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0answers
47 views
Why bash need job control?
Why Unix systems need job control?
So for example, we can use the process number or job number(jobspec) with the kill command.
$ sleep 101 &
[1] 19
$ sleep 102 &
[2] 20
$ jobs -l
[1]- 19 ...
0
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1answer
32 views
how does a process group have process id?
I'm reading a textbook which discusses process group and shell and it says:
Unix shells use the abstraction of a job to represent the processes that are created
as a result of evaluating a single ...
0
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1answer
33 views
Three Questions on Child Shells: Lifespan and Creation
Is a child shell's life over shortly after it's created? I.e., do its assets get replaced by the process that is going to be run in it? Say we've run grep -r "something" in bash, so our ...
2
votes
1answer
144 views
Does /proc/ contains tid?
I have process id 1234. This process contains thread id 1235.
When I use ls -l /proc I see only the pid (1234) but when I open the thread status file using cat /proc/1235/status I can see data.
Why is ...
0
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1answer
27 views
How to find out on which core a thread is running on?
Let's say we have a CPU-intensive application called multi-threaded-application.out that is running on top of Ubuntu with a PID of 10000. It has 4 threads with tid 10001, 10002, 10003, and 10004. I ...
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0answers
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Stop automatic application execution on graphical login
I use Manjaro 20, and have changed the display manager from LightDM to SDDM, out of that and installing normal applications, I haven't changed anything on the system.
For some reason xfce4-terminal ...
3
votes
2answers
280 views
When I do double fork a process, is the detached process still in the same process group?
As titled, extra question, can process group have descendants?
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0answers
55 views
“-bash: fork: retry: No child processes” - but why?
So this is not about too many processes for the first check:
SERVER:/proc # ls|wc -l
672
SERVER:/proc #
load isn't big
SERVER:/proc # uptime
20:03pm up 19:29, 1 user, load average: 0.90, 1.64, 2....
1
vote
2answers
55 views
How to start a realtime process?
I looking for a way to start a real-time process or set a running process as a real-time process.
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2answers
37 views
Stop specific processes from heating up my system's CPU
I have a process doing some computation the whole time. It causes my system's CPU to heat up and the fan to spin faster.
I want this process to run, but with a low priority. I don't want my system to ...
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0answers
36 views
How to kill a Python process within an SSH session
This question involves running a bash script, say helloworld.sh, which executes an MPI mpirun command which in turn runs a Python program, say helloworld.py, using mpi4py. The bash command is used in ...
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2answers
84 views
Is it possible for a kernel space thread or process to be child of a userspace process?
I am kind of a newbie when it comes to the Linux Kernel, but I was reading this article about fibrils where it mentions that they are (or were? not sure if they were ultimately kept in the Kernel) ...
0
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1answer
60 views
Why sometimes when i run a program in terminal, it won't run in the terminal?
Suppose i have two applications called firefox and arduino. At first, I typed firefox to the terminal and i still can use the terminal as usual. But when i typed arduino , i couldn't use the terminal ...
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2answers
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best range for custom exit code in linux? [closed]
Here I am developing an application that can exit for various custom reasons. What is the best range for a custom exit code (like 150-200)?
I know this opinion-based but still i wanted to know the ...
0
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1answer
25 views
Automatic Process kill process problem
I am using MX linux for a few days and I found a problematic behavior. Suddenly sevaral processes were killed automatically. For this, I had to face many problems. Is there any way to stop it? I don't ...
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0answers
37 views
How to open a running instance of a program in Debian?
When I try to open VeraCrypt I get this error: VeraCrypt is already running.. How can I open the running instance?
0
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1answer
22 views
what will happen if receiver unable to handle data velocity through socket?
I have two processes P1 (sender) and P2 (receiver). P1 uses unix-domain-socket (UDS) to send data to P2. what will happen if P1 sends data at the rate of 100 messages/second and P2 is capable to ...
1
vote
1answer
45 views
PID of a nested command in a subshell
Okay, I've got a program I'm trying to fix, for lengthy reasons a rewrite isn't the greatest option... So, I've been up for 8 hours trying to solve this and I'm completely stumped.
I'm trying to get ...
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0answers
16 views
How to retrieve a process cmdline after setproctitle?
I tried looking at how sshd spawns its processes and caught something like sshd: [priv] in the process list. When I tried reading /proc/pid/cmdline I got the sshd: [priv] name but I was wondering how ...
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0answers
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Get the script command of a child process?
Is there a way to retrieve the script command responsible for a child execution?
For example:
If I run in a script called runX arg1 arg2 (X being the process name)
[some code]
X arg3 arg4
now when I ...
0
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0answers
21 views
Keeping the process alive after launched passing command to gnome-terminal
I'm trying to keep alive the TimezoneClock process after that I've passed the commands to gnome-terminal. Before I've tried without the terminal for the start-up but it doesn't works, then now I'm ...
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votes
1answer
28 views
Port 3000 is always being hogged by grafana-server
I need port 3000 free for my dev work. But it's being used by grafana-server, that I don't remember ever installing. We do use it within our company so perhaps at some point it has been added to ...
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0answers
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SIGSTOP anything I haven't interacted with in 10 minutes?
For working on multiple projects, I may open several applications in separate workspaces.
It's possible that while I'm working on one thing, the other set of applications are open but not in use. I ...
0
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1answer
43 views
How to bring sleeping process back to foreground?
I used ssh to connect to a server, and run a process in docker.
docker exec -ti docker_name /bin/bash
However, the ssh connection broke at some point, when I went back, command top shows
PID USER ...
0
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0answers
26 views
Using coprocess to write a name referenced variable in BASH
I currently try to start background process with coproc and update a name reference variable.
My not working code:
function updateVariable(){
local -n myVar="${1}"
#i=0;
while :
do
...
0
votes
1answer
36 views
What happens to a bg process after a shell is exited?
What happens to a &ed process after the parent shell is exited?
some-daemon &
killall "$SHELL"
is the daemon killed? what signal is sent to kill it then?
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0answers
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Change the GID of an existing process [duplicate]
Is it possible - for a privileged process - to change the GID of another process. I know that there is the setgroups() system call that allows a process to change it's own GID. However, I want to do ...
1
vote
1answer
145 views
kdevtmpfsi process is using 100% CPU, restarting on kill
I have amzon linux instance with docker, rabbitmq and ejabberd installed.
One process is starting and using cpu 100% I'm trying to kill that process but after sometimes it is starting
Top command ...
2
votes
3answers
106 views
How do I force-close all active ssh sessions that were started by a specific sshd daemon?
I have a system that runs multiple sshd daemons. Each daemon listens to a separate port.
How can I terminate all sessions started by a specific daemon without affecting other ssh sessions?
1
vote
1answer
30 views
How to prevent the program from accessing files?
I want to run some proprietary software on my Linux machine, skype for example. But I do not trust this program and I want to block for this program access to some folders in my home dir.
I tried to ...
0
votes
1answer
23 views
Why does a user session have to be completely closed when groups change? [duplicate]
Adding a user to new groups in linux is easy -- you just need the following command:
# adduser user group
But this doesn't really do anything till you log off and then log in anew. When you have a ...
0
votes
1answer
45 views
How to get this list? Don't miss any [PID] (running & ended)
How to get this list (table)?
From turn on the computer until now.
Don't miss any [PID] (still running [PID], already ended [PID]).
List field: PPID, PID, Threads, USER, Start-time, Change-time, End-...
1
vote
1answer
30 views
Is it possible to read a .sh that was deleted from file system but is being executed? [duplicate]
I've received a project that some dude did and it's on production stage. But that guy had some issues with project managers and other team members (bad attitude, being an ass.. etc). Intentionally he ...
1
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1answer
17 views
How can I perform a partial matching of the command name using `ps -C`?
I find the ps -C <cmd> option very useful, since it lets me limit the output of ps to only those processes started with command name <cmd>.
Compared to performing a grep, I also get the ...
2
votes
3answers
80 views
Pause and resume application
I can pause and resume a process by sending it the SIGSTOP and SIGCONT signals.
Taking Firefox as an example:
pkill --signal SIGSTOP firefox
pkill --signal SIGCONT firefox
The thing is that Firefox ...
0
votes
1answer
46 views
Terminate anonymous pipe when “output” process exits
So let's say I have something like this in a shell script
command1 | command2
Now how can I make it so that command2 terminates when command1 exits?
Edit:
That usually happens by default when ...
0
votes
0answers
22 views
How to deal with a MacOS process in the W state?
htop man says W for paging. I see a process with this state. Is there a way to get it out of that state and back into the running state?
0
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2answers
33 views
Two processes are running for VNC Service in RHEL 8.2
I have a user account 'virendar' where I have configured vnc. And I noticed, even two processes. I have tried killing two processes and within few seconds, I see one process is getting started ...
