A process is an instance of a computer program that is being executed.

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How can I know threads names that run on specific core

I am working in java code,my code attend in making specific java thread run on specific core and in this code i give names for java threads.I need linux command that enable me to know threads names ...
3
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1answer
43 views

Why can the waitpid system call only be used with child processes?

The man page wait(2) states that the waitpid system call returns the ECHILD error if the specified process is not a child of the calling process. Why is this? Would waiting on a non-child process ...
2
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1answer
48 views

How to kill a task that cannot be killed (uninterruptable?)

I have a task running that blocks pm-hibernate (on Linux 4.0.7-2). When I try pm-hibernate there is an error message "Freezing of tasks failed after 20.002 seconds (1 tasks refusing to freeze, ...
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2answers
42 views

bash + how to hold shell scripts

Is it possible to hold/stop the bash script progress without to kill the process? ( by kill command ) or other command For example this script - install_linux_pkgs.bash , will install Linux pkgs ...
2
votes
3answers
830 views

Check that fail2ban is running?

I just installed and configured fail2ban. I want to make sure it is working. I don't want to block myself from the server so I can't just login (poorly) a bunch of times. How do I see that fail2ban is ...
2
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2answers
47 views

How do I kill a process after detaching it from bash?

I have multiple scripts that detach a process from bash using nohup and &>/dev/null &. My question is, how do I kill the process after completely detaching it from bash. using killall or ...
1
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1answer
78 views

Why does my process take too long to die?

Basically I'm using Linux 2.6.34 on PowerPC (Freescale e500mc). I have a process (a kind of Virtual Machine that was developed in-house) that uses about 2.25 G of mlocked VM. When I kill it, I notice ...
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1answer
50 views

Process command

When I used ps -u root command in Ubuntu it showed the following output? PID TTY TIME CMD 1 ? 00:00:02 init 2 ? 00:00:00 kthreadd 3 ? 00:00:00 ksoftirqd/0 5 ? ...
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50 views

Find which process is being joined by another?

If I have open Nautilus and spawn a new Nautilus instance a new PID is created for the new Nautilus instance. Shortly after, the instance is being joined with the main Nautilus program running. Main ...
1
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1answer
51 views

Is there a robust way for a child process to signal readyness to its parent? [closed]

I have a (Java) process which is staring a separate process foo. foo takes some number of seconds to start up, then is really running. Control returns back to the parent process as soon as foo is ...
2
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1answer
83 views

list processes belonging to a network namespace

I am on Ubuntu 12.04, and the ip utility does not have ip netns identify <pid> option, I tried installing new iproute, but still, the option identify doesn't seem to be working!. If I were to ...
21
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1answer
574 views

What does it mean to have a minus sign as the first character of a command in htop output?

In htop, or other commands that show process status, all bash processes have in the command column /bin/bash but one process has in the command column -bash What does it mean?
9
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1answer
936 views

Still alive, still alive after kill -9 / SIGKILL [duplicate]

An apache2 process got stuck on my server and caused problems with other services. (original problem: kerneloops after USB hardware disconnect) root@server:~# ps aux | grep apache2 | grep -v grep ...
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0answers
18 views

Inconsistent output on /proc. Can some processes be hidden? [duplicate]

When I list /proc/<PID>, works as expected. But when I use ps or ls /proc | grep <PID>, the process is hidden. How & Why is this possible? [user@host ~]$ ls /proc/12263 attr ...
9
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1answer
81 views

Is it possible to know the source (application) of the clipboard?

I've noticed that sometimes clipboard contents become unavailable if the source application (where the content was copied from) is closed. This leads me to wonder if it's possible to know what the ...
2
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1answer
76 views

Process startup after boot

I know the following are ways processes get started in Linux from init.d (or similar) from shell (by user) forked by a running native daemon Is is ever possible on Linux for a process to be ...
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2answers
74 views

Why is the range of load average not 0-1+ for all cpu's together?

I know that load average is 0-1(or 0-1024) per cpu. E.g a busy quad-core can have a load average of 4.0 or higher. (e.g if there are many tasks). I understand it can be huge like 100+ etc. I also ...
14
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7answers
22k views

Kill many instances of a running process with one command

This is one of the questions that has troubled me often. Suppose I have thousand or more instances of any process(for e.g. say the process vi) running. How do I kill them all in one single shot/one ...
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1answer
35 views

How can I find out which mounted filesystems a running process sees?

After having a long debug session and finally finding out that in Fedora (and CentOS) php-fpm has its own mounted /tmp filesystem, which was caused by a systemd setting, PrivateTmp, I am wondering if ...
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0answers
19 views

Page Fault Frequency Algorithm - Compute number of frames and mean resident set

I'm reading about Page Fault Frequency algorithm but I don't understand how can I compute the number of frames. For example I have my reference string: 112233444412412214432255543 and control ...
0
votes
1answer
35 views

Kernel current working directory and inode information placement

I'm reading some doc about UNIX but I don't understand two things: Why is important for the kernel to know the current working directory of the running process? Why not keeping the inode information ...
2
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6answers
375 views

How to close all proceses without restarting a machine?

I have a lot of processes running and I need to kill them all. How can I do this without restarting a machine?
6
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4answers
3k views

chdir(<directory>) doesn't change directory after exiting to shell

I wanted to make a simple C program to change to my project directory. Its content is as follows: #include <unistd.h> int main() { chdir("/home/enedil/projects/algo"); return 0; } I ...
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1answer
32 views

Stopping jobs by PID?

Could someone tell me why I am unable to kill the jobs below when specifying their PID? I can stop the jobs when using their % id. Mac:~ gd$ ps PID TTY TIME CMD 4523 ttys000 0:00.02 ...
3
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1answer
48 views

Sending signals to long-running processes (AWK, DD)

I'm familiar that DD command doesn't produce output while running. However, if I send a USR1 signal to it, it can print current state. Can I do the same with AWK? Prints its variables, register ...
3
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2answers
56 views

Sum the memory usages of all the processes of a program?

How can we sum the memory usages of all the processes of a program? For example, I have opened many Chrome tabs for webpages, and each tab runs a different process. How can I get the total sum of ...
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1answer
38 views

Show CPU core usage for parent process and its child processes

Is it possible to display CPU core usage just for a single process and its child processes on Linux?
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2answers
382 views

How to locate a Chrome tab from its process PID?

I opened many Chrome tabs for webpages. Each tab has its own PID, e.g. USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND t 3900 1.9 6.3 5718440 508660 ? Sl ...
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votes
2answers
102 views

What to do when “nice” isn't good enough (FreeBSD)

I've been using x265 to encode some video on my workstation lately, but I have a problem: even though I launch it using nice -n 20 x265 to deprioritize it, it still slows the computer to a crawl while ...
2
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1answer
28 views

How to guard a set of folders from being written into by a specific process?

I would like to have a way in which a set of folders do not allow write access for a particular process. For example, I would love to have a way in which YUM/RPM is not allowed to write into /usr/bin ...
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votes
5answers
5k views

Why teamviewer starts again after being killed

My main desktop has Mint 14 and I approached it via SSH from another computer, because I didn't have a screen on the Mint one. Then I tried to start teamviewer just I order to launch its desktop ...
3
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2answers
42 views

How to update user/group settings of a running process?

Suppose I change some user settings like its initial login group or add it to a new group. I now can do su user and work with these new settings. But all the previously running processes will still ...
3
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3answers
659 views

How to restart (or reset) a running process in linux

I have two Linux systems communicating over sockets (Desktop and ARM-based development board). I want to restart (or reset) my client application (running on a development board) when server sends a ...
3
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1answer
63 views

what does it mean 'fork()' will copy address space of original process

I'm studying 'operation system concepts' on my own and I'm studying the chp3. process part. There is an example where the 'fork()' function is called and depending of the returned pid value like the ...
5
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1answer
5k views

Is it possible to get process group ID from /proc?

In "http://stackoverflow.com/questions/13038143/how-to-get-pids-in-one-process-group-in-linux-os" I see all answers mentioning ps and none mentioning /proc. "ps" seems to be not very portable ...
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2answers
61 views

Why do some processes end with the letter “d”? [duplicate]

Some Linux binaries end with a "d", for example sshd, httpd, ppd, etc. Why is this so?
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31 views

How do I automatically kill the process and restart it to use the updated package? [closed]

Suppose a process is using a package, and I update it in the midst. How do I create a trigger in Linux that automatically kills the process and restarts it to use the updated package
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If processes can't modify their parent's environment, what is MC doing?

As far as I know, a process cannot modify its parent's environment. However, when I run mc (GNU's Midnight Commander, a curses-based file manager) and then quit it, I end up with another $PWD: ...
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4answers
108 views

How do I get the value of a named option of an already running process in Linux?

I run the following command. ps -e -o args | grep destiny | grep UNIX I receive the following output. /path/to/destiny -r -m UNIX -t TCP -p 1501 What command can I use the get the value of the ...
5
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1answer
78 views

How to enable random PIDs on Linux?

I'm currently comparing random PID implementation on OpenBSD, FreeBSD and Linux from security perspective. As long as OpenBSD and FreeBSD are concerned, my work is done. However, while the answer ...
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vote
1answer
149 views

Can a script be running even after it's been killed?

I know it sounds so stupid, and I know it IS stupid; but I ran a Unix script to send me and my friend emails every few seconds to test mailx. The stupid thing is I used $ while true; do blah blah ...
3
votes
3answers
361 views

How do I know if acct is running? (The Unix system accounting)

I have installed the acct package and it is running because I can see file activity in the log file. I know there is the command accton on to turn it on, but how do I determine that its running short ...
2
votes
1answer
509 views

Does jps lie? If not, what else is this?

I am running dockerized hadoop cdh 4.6.0 with supervisor . I have opened the docker container and tried the following two commands. Got confused a lot. jps 103 -- process information unavailable ...
14
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3answers
1k views

Is there an upper limit to the number of zombie processes you can have?

I used to work with an HP-UX system and the old admin told me there is an upper limit on the number of zombie processes you can have on the system, I believe 1024. Is this a hard fact ceiling? I ...
6
votes
3answers
461 views

How do Linux permissions work when a process is running as a specific group?

This is something I haven't been able to find much info on so any help would be appreciated. My understanding is thus. Take the following file: -rw-r----- 1 root adm 69524 May 21 17:31 ...
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Is there any considerations I should take when running untrusted apps as non-root user?

I have to use an application I don't trust (unstable) and I will run it as a non-privileged user so if something bad happens the damage would be limited to the home folder of that user. I removed ...
3
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1answer
35 views

Get all files open for writing with pid, recursively

Given a pid, I can get all the files open for writing something like: lsof -p 28827 | awk '$4 ~ "[wW]"{print $(NF-1), $NF}' One of those ends up being a pipe: 28827 232611 pipe I want to look-up ...
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3answers
22k views

Which process has PID 0?

I'm looking for the process started in Linux which has process ID 0. I know init has PID 1 , which is the first process in Linux, is there any process with PID 0?
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1answer
94 views

How are zombie processes handled when the parent dies?

Which technique does the Unix system use to remove zombie processes whose parent has terminated?
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4answers
289 views

Are the states of processes which are ready and scheduled to wait “S”?

In the output of top, the state S means interruptible sleep. What is the state of those processes which are scheduled to be ready and waiting for execution in CPU by the scheduler? Is it S or ...