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

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How can I find which process sends data to a specific port?

I have a service, keeping a certain port open. I'm getting data to it, that I neither expect nor want to get, and I'm trying to pin-point the source of this data. So how can I find which process that ...
1
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2answers
671 views

How to run linux process and come back to it later?

I'm trying to run a minecraft server on linux. Running the server starts an important interactive session. I can run the server in the background by appending & at the end of the command and log ...
1
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0answers
38 views

Modify environment variable in a running process [duplicate]

Possible Duplicate: change environment of a running process Is there a trick to modify an environment variable in a running process? I need to add a repository at the end of PATH. I have ...
2
votes
1answer
68 views

remotely query text file associated with an instance of vi

I have opened several text files (a.txt, b.txt, c.txt, ...) in different sessions of vi launched from different instances of a bash shell. Having then accessed that machine remotely, I wish to ...
3
votes
2answers
9k views

Get PID of a function executed in the background [duplicate]

#!/bin/bash function abc() # wait for some event to happen, can be terminated by other process { sleep 3333 } echo "PID: $$" abc & echo "PID: $$" I need to retrieve the pid of this function, ...
13
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4answers
4k views

Suspend/resume single process to/from disk

On occasion, we would like to suspend memory-intensive processes on our Ubuntu and OS X servers to temporarily free up some RAM for other jobs. If all we were worried about was CPU usage, a simple ...
9
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1answer
13k views

Stuck process: is it a bad sign?

Sometimes a few process are in a stuck state. For example: PID COMMAND %CPU TIME #TH #WQ #POR #MREGS RPRVT RSHRD RSIZE VPRVT VSIZE PGRP PPID STATE 99357 plugin-container ...
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3answers
1k views

What process is sending TCP SYNs on Solaris 10?

Some process on my Solaris 10 machine is sending TCP SYNs to a remote machine. The remote machine never responds, so the connection is not established. How do I find out what process is initiating ...
2
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2answers
649 views

How to stop a infinite running process (ztail) started by a ssh session after that session is closed

I have a peculiar problem. My server supports multiple ssh session simultaneously, so that multiple admins can manage (via command line interface) it simultaneously. We have a command which calls ...
4
votes
3answers
950 views

Why does a default Linux installation run more processes than a default OpenBSD installation?

If I ps -aux on Ubuntu (or any GNU/Linux distribution) without GUI I see ~100 processes running. If I ps -aux on OpenBSD without GUI, then I get ~10 processes. What is the explanation/reason for ...
1
vote
1answer
222 views

Is there any way to attach latrace to an already-running process?

I want to trace a running multi-threaded process's library calls. As of 5 November 2012, there's only one way to get ltrace to fully support tracing multi-threaded processes: you must check out and ...
2
votes
1answer
926 views

Korn shell timeout/kill script

I am trying to write a simple Korn shell script to execute a loading process. The process occasionally runs into connectivity issues, so I need to kill it if it runs too long. I have been trying the ...
5
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2answers
281 views

How to kill a process giving it a number of seconds before a doing the forced kill?

I do have the PID of the process to be killed but I do want to give it the chance to die peacefully, without doing a -9. Expected behaviour: check if PID is still running for up to ten seconds and do ...
21
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3answers
1k views

Can other users view the arguments passed to a command?

If I invoke a command with arguments like so: bob@bob-pc:~$ command -arg1 -arg2 ...can other users view the arguments passed to the command?
3
votes
1answer
189 views

how to disallow user to change process group

Is it possible to restrict a process from changing it's process group? For example, user nobody seems to be able to call setpgid(0, 0) which sets process group of current process to pid of that ...
1
vote
2answers
808 views

How can I disable /proc pseudo-filesystem on a shared Linux environment?

Is it possible to disable the /proc pseudo-filesystem to prevent w, ps, top, etc, from showing what other users are doing? Of course, I still want "everything else" to work correctly. Is there a ...
3
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1answer
1k views

When do jiffies increment? How a process runs in a jiffy?

I know that jiffies length is selected at kernel compile time and it is defaulted to 250 (4ms). Source: man 7 time - The Software Clock, HZ, and Jiffies I wonder what happens inside a jiffy. What are ...
5
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1answer
2k views

root owned program with setuid bit on

Ping is a a program owned by root with the user id bit set. $ ls -l `which ping` -rwsr-xr-x 1 root root 35752 Nov 4 2011 /bin/ping As I understand it, if a user runs the ping process, then the ...
2
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4answers
173 views

How to find out what is this process for?

I have this 'java' process running for 3 hours ( I guess ). I didn't see it before and I wonder how could I find out where it's coming from? Here is a screenshot: EDIT: ok I figured it out, it's ...
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1answer
2k views

What is the advantage of using pthreads in Linux?

I read somewhere that Linux threads are really implemented as processes in the kernel since with today's hardware and on the Linux platform, the thread model is inefficient compared to the process ...
3
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0answers
204 views

Can I get WCHAN from ps on Mac OS X 10.7.4?

From the manual it seems that ps -AO wchan should tell me what everything is sleeping on, but everything comes up as -. (And nwchan as 0). Did they do away with the old sleep()/tsleep() interface in ...
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3answers
118 views

What is the lowest level I can see my system running?

Let me try and clarify. Is there any way for me to see very very low level activity on my computer? Stuff like: register content opcodes being sent specific memory addresses Or anything lower ...
2
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2answers
2k views

Find the PID of top CPU/MEM usage, save to a shell variable

Is there any way to get the PID of the top CPU/MEM usage, I need to use that in a script, top command doesn't seem to work for it.
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3answers
383 views

Where to find explanation of kernel processes?

I want to know about kernel processes, like [migration], [kswapd], etc. Where are kernel processes like these documented?
0
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1answer
372 views

Where can I see the processes running at startup?

I'm using backtrack5 R2 and sometimes when I log in the information showed says that There is 1 zombie process, where can I see what process is running?
5
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2answers
1k views

Why is `sudo pkill -HUP -f “nginx: master process”` returning code 129 and no output

I'm trying to trigger a reload of the Nginx master process by using pkill and sudo. The server reloads fine, but I was just curious if anyone knows why the command sudo pkill -HUP -f "nginx: master ...
6
votes
1answer
6k views

Find processes using a network interface

I'm trying to find a way to safely shutdown a network interface, i.e. without disturbing any processes. For this I need to find out what processes are currently using that interface. Tools like ss, ...
2
votes
2answers
172 views

How to constrain the resources an application can use on a linux web server

This is the situation: I have a PHP/MySQL web application that does some PDF processing and thumbnail creation. This is done by using some 3rd party command line software on the server. Both kinds of ...
3
votes
3answers
566 views

Prevent users from killing processes that they own

I have started some processes (window based) from user's .bashrc file. I want to prevent users from killing those processes. Is there a way to transfer the process to superuser so that a normal user ...
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vote
1answer
5k views

How to know maximum memory usage of a process? [duplicate]

Possible Duplicate: Measuring RAM usage of a program I have a process, which is quite short-running (about 10 minutes), but memory heavy. I want to know how much memory does the process ...
3
votes
1answer
1k views

How do I detach a process from its parent? [duplicate]

Possible Duplicate: How can I disown a running process and associate it to a new screen shell? The problem is that the process is not a job inside of my active shell (as I've logged in from ...
4
votes
1answer
930 views

What process created this window with no PID associated? [duplicate]

Possible Duplicate: What process created this X11 window? I need to kill a process that spawned a window which seems to have no PID associated with it. At least that is what xdotool says: ...
2
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0answers
165 views

How to find current chroot jail path on Linux <2.6.26

While running kernel 2.6.26 or newer it's possible to get the path of the current chroot jail by comparing the mountinfo of the current process and the init process. Is there a way to get the same ...
2
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1answer
594 views

How to log processes in daemon-mode?

I would like to save the standard output of the program motion in a text file. If I don't use motion in daemon-mode I would simply do it by: motion > log.txt But what is the equivalent when I ...
5
votes
1answer
5k views

mmap() failed: Cannot allocate memory - how do I find out who's complaining?

mmap() failed is popping up in my .xsession-errors in bursts. But there's no indication about what application it is failing with. How do I look into this after it has happened? I usually discover the ...
3
votes
2answers
186 views

How to detect out-bound port from PID

I have several applications that run on random ports. How would I take the pid or the file location and find which port it is running on? Example of desired output: www-data/apache = 80 ...
6
votes
2answers
5k views

Write inside a socket open by another process in Linux

Is it possible on Linux for a process to write inside a socket open by another one? Let's say I open a connection to google.com using netcat: myuser@linux:~$ nc google.com 80 Now I can lookup for ...
3
votes
3answers
337 views

How do I see more of the command line with the KDE System Guard Process Table

I often have several java programs running and I can't tell which one needs to be killed. The command section of the process table only shows java, but doesn't tell me which jar or class files it is ...
6
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2answers
2k views

Hide processes from other users based on groups (under Linux)?

Is it possible to configure process hiding for certain user groups under a linux system? For example: Users from group X should not see processes owned by users from group Y in ps/top or under /proc. ...
34
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4answers
8k views

Save entire process for continuation after reboot

I developed an algorithm for a fairly hard problem in mathematics which is likely to need several months to finish. As I have limited resources only, I started this on my Ubuntu 12.04 (x86) laptop. ...
0
votes
1answer
420 views

Giving input to background processes

Is there any way to give input to background processes or which run as daemon processes? I was coding some Puppet configuration files and I had to push them to some remote machine. For that purpose I ...
5
votes
1answer
3k views

Difference between poll_s and ep_poll WCHAN in ps output

When I issue ps -elf|grep python for example on my system, I see these: 1 S 1000 6020 6008 0 80 0 - 9914 poll_s Jul12 ? 00:00:01 python manage.py run_gunicorn -t 3600 -w 8 -b ...
42
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3answers
18k views

What are “session leaders” in `ps`?

What are session leaders, as in ps -d which selects all processes except session leaders?
2
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1answer
216 views

Set a callback for when a certain process is spawned

The script I'm writing launches process A, which after an uncertain amount of time, launches a child process B. I need the script to execute a command C which depends on process B. But B might not be ...
4
votes
2answers
3k views

Linux running slow with 0 swap left

Our Linux server is responding very slowly. top doesn't show any excessive CPU usage. I noticed that even though there's about 5GB of free memory, the system is using all of swap with no free swap ...
22
votes
2answers
895 views

When you try to terminate a process for good, which option for “kill” should you use?

I am getting a lot of mixed messages from people, and was wondering if it there really is not much of a difference in what you use. kill 'x' killall 'x' kill -9 'x' These are some options I've been ...
4
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1answer
730 views

Rationale for making user space text segment start at 0x8048000

I read somewhere that (at least since Linux v. 2.6) all user-space code is placed at load address 0x8048000 in the virtual memory address space. My own observations confirm this. I have done a cat ...
3
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2answers
1k views

How can I kill the top CPU/IO process quickly?

I find that sometimes my Linux will stop responding, so I need to switch to another terminal with CtrlAltF2, and type a command to kill the top CPU usage process or top IO usage process, so that the ...
2
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1answer
228 views

How can I log what software I use the most?

I really like using open source software and would like to help fund further development. Unfortunately, I have limited funds to do so. Being somewhat greedy, I would like to donate to the projects I ...
3
votes
3answers
166 views

Detecting whether a server is loaded

I have to start some performance test on a Rhel 6 box, but before starting the test, i have to make sure there are no other java processes running. The manual way of doing it would be to use "ps -ef ...