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

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How to get a process uptime under different OS?

Under Linux I can get a process's uptime in seconds with: echo $(($(cut -d "." -f1 /proc/uptime) - $(($(cut -d " " -f22 /proc/$PID/stat)/100)))) But how can I get it under different OS? ex.: ...
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Finding the ID of a process and killing it

When ever I need to kill a background process I do ps -e | grep <process_name> Which prints something like this 1766 ? 00:00:13 conky , Then I use the process ID to kill it like so kill 1766 . ...
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1answer
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Limit process resource consumption in CentOS 5 (2.6.18 kernel)

I would like to limit the resource (CPU, Memory, and network bandwidth) consumption of processes on the same server. And it will be good if I can migrate processes from one server to another. I ...
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1answer
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Will process ids be recycled? What if you reach the maximal id?

Process IDs are strictly increasing, but if your system runs long enough and there is a lot of processes terminating and starting, you could at some point reach the limit of the underlying integral ...
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3answers
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Why is apache2 showing up a defunct in the process list?

When I run top I see one line that doesn't look too good: 2475 www-data 20 0 0 0 0 Z 1 0.0 0:00.19 apache2 <defunct> Why is this process <defunct> and what should I ...
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2answers
615 views

Why does my one instance of VLC have many processes?

As you can see from the image below (htop), I have several vlc processes running, all with only the command vlc. However, I'm only running one vlc instance. What are the other instances? Would it ...
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2answers
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killing a process on a remote machine when the machine is stuck

I started a very resources-consuming process on a remote server via ssh. It is an optimization problem run in MATLAB. It takes full memory and CPU. In fact, I am not even able to ssh to the machine, ...
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1answer
637 views

Enter process running in background/bring to foreground [duplicate]

Possible Duplicate: How can I disown it a running process and associate it to a new screen shell? I started a java client using nohup to get it to run in the background (needed to log out ...
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0answers
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Rogue Java process brings my computer to a halt

In reference to my earlier post: Is there a log of past threads that are now closed? I gave the process a kill -STOP signal and started examining the details. I can't seem to figure out why it is ...
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2answers
503 views

Is there a log of past threads that are now closed?

Sometimes, I have a rogue Java process which takes up 100% of my CPU and makes it jump about 30C in temperature (usually resulting in a crash if not killed). Problem is, I can never really identify ...
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117 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 ...
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nohup vs. Screen

In the past, I've used nohup to run big background jobs, but I've noticed that a lot of people use Screen in this context. Does Screen provide some kind of functional advantage that I am unaware of, ...
2
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2answers
473 views

add “check if fetchmail is running” to this script

while ! postqueue -p | grep -q empty; do sleep 1 done killall wvdial this script checks if my mail queue is empty, then disconnects my modem. now i would like to add also a checking to fetchmail ...
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2answers
8k views

How to pkill by “command name”?

So I'm executing a command like: COMMANDNAME -PARAMETERS But..why can't I kill it with "pkill"? I'm trying with: pkill -9 "COMMANDNAME -PARAMETERS" but it doesn't kills the "COMMANDNAME ...
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3answers
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What is a subshell (in the context of the documentation of make)?

I'm reading a book about the make command and there is a paragraph: If any of the prerequisites has an associated rule, make attempts to update those first. Next, the target file is considered. ...
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1answer
160 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 ...
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3answers
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How to stop a bunch of processes on unix fast?

How to stop a bunch of processes on unix fast. I can use ps/top, kill. If the number of processes is very large, I use shell script. Are there other ways, only one or two unix commands can do it ...
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2answers
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How to check, which limit was exceeded? (Process terminated because of ulimit. )

Let's assume process runs in ulimited environment : ( ulimit ... -v ... -t ... -x 0 ... ./program ) Program is terminated. There might be many reasons : memory/time/file limit exceeded ; just ...
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2answers
651 views

How is FireFox running on a virtual machine that has no display?

I am using a Red Hat virtual machine, accessible only remotely. However when I use the top command, one of the displayed processes taking up the most memory is firefox, located at ...
2
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1answer
581 views

There is no bash indicator prompt after a forked process terminates

I am reading the book Advanced Programming in the Unix Environment. There is a test program to test the fork function. It works well in my Ubuntu. But what I confused is that why there is no command ...
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2answers
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Limit process to one cpu core

How to limit process to one cpu core ? Something similar to ulimit or cpulimit would be nice. (Just to ensure: I do NOT want to limit percentage usage or time of execution. I want to force app (with ...
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4answers
3k 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 ...
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1answer
147 views

Start and stop multiple executable for easy debugging

I'm debugging a networking project, which involves interacting of 3 programs, ie a server, two different clients. However I find it difficult to start and stop them for debugging. Some methods I have ...
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1answer
644 views

rpc.statd and avahi-daemon listening on all networks?

Background: - I'm running a home Debian GNOME desktop connected to the internet through an ethernet cable to an ethernet router. - I have a printer connected directly to my PC with a USB cable. - My ...
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2answers
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Do sleeping processes get the same CPU time?

Some processes spend most of their "lives" in a sleep status. Daemons, servers and general listener come to mind. I was wondering if they get the same CPU time in that state? On something like my ...
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What's the best way to determine the working directory for UNIX process using 'ps'?

I am running a Ruby command line script (rufus.sh)which ultimately calls Thread.new, which spawns a UNIX process as shown below. I run this script for more than 1 directory as the output of the ps ...
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543 views

why new pid is smaller than the old ones?

Is there any chance the new process's pid is smaller than the existed ones ? I have a daemon process which will restart when be killed, I recorded the pids, and found that the pid first came smaller, ...
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What is the need of the struct thread_info in locating struct task_struct?

While reading through the Linux Device Drivers, I could understand that the Process Descriptor (of type struct task_struct) has all the info regarding a particular task. The process descriptors are ...
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1answer
810 views

controlling a process from a different session

So, I ssh into my remote computer and launch a process... time passes... my ssh session breaks. I log in again, and of course, I don't have access to the original process now. I can see it still if I ...
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What do the brackets around processes mean?

mark@mark-VirtualBox:~/auto/lib$ ps -Awwo pid,comm,args PID COMMAND COMMAND 1 init /sbin/init 2 kthreadd [kthreadd] 3 ksoftirqd/0 [ksoftirqd/0] 5 ...
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2answers
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Launch process as another user/group (in init.d script)

I am editing a init.d script. The init.d script runs a utility script which then runs an process. From either bash scripts how would I make it launch the main process as a specific user and group?
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1answer
417 views

Return value of a process and comparison of the number

I have a val.py python script that returns a negative number. import sys sys.exit(-1234) When I run this bash script, I get the value $? as return value of 46 (not -1234). Even when I tried to ...
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2answers
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lsof for a specific process?

There's a bzip2 process running in the background and I have no idea where it came from. It's eating up a lot of resources. Can I do a reverse lsof to see which files are being accessed by this ...
5
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1answer
579 views

How can I search/browse in some process's memory?

I'm using MacOS X 10.7 and I'm not very familiar with unix. Is there a command for a search in some process's memory for a string?
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1answer
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Getting disk i/o statistics for single process in Linux

I need to monitor the I/O statistics of a process that writes to disk. The purpose is to avoid write rates too high for long periods. I know there's iostat tool to accomplish this task on a ...
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5answers
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Drop Process Privileges

I have a process that gets started by a damon running as root, now I want to "downgrade" this process's privileges to those of your average user. Is this possible? If yes how? PS: Running unix on a ...
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Under AIX, how can I get the full path of a program bound to a port?

Under Linux I can use netstat -tulpnw and ps, like so: # netstat -tulpnw | grep :53 tcp 0 0 127.0.0.1:53 0.0.0.0:* LISTEN 1482/named udp ...
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1answer
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How do you make a cross-process locking in Linux (C/C++)?

I need to make sure one process executes only in one instance at a time. On Windows you could use named mutex. But I have no idea what to use on Linux. I think I've seen an approach were app creates ...
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How to find which Process is causing High CPU usage

Is there any way to find out from terminal which process is causing high CPU Usage ? It would also be useful to order processes in descending order of cpu Usage
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3answers
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How can I test if a program is running from within a script

Let's assume that another user started a bunzip process, and I have a script that I'd like to start running after that bunzip finishes. What's the best way to check from inside my script that the ...
3
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4answers
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How to run java process to be seen not as 'java…' in processes list?

Is it possible to run a Java process in Linux in a way that it could be seen in ps as some sort of alias? It would be easier to restart it when it is down.
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1answer
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All about ssh ProxyCommand

I am looking for an in-depth explanation of the following ProxyCommand, down to the nuts and bolts of its operation, please. Can you kindly completely dissect it for me and improve on it if you can? ...
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1answer
735 views

Using `pidof` with `sh -c`

I was wondering why this command line does not print pidof sh: $ sh -c "var=`pidof sh` ; echo \$var; ps -H" This one prints 123 as expected $ sh -c "var=123 ; echo \$var; ps -H" I am on Ubuntu ...
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3answers
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Simple queuing system?

Given a commodity PC, we would like to use it to execute some tasks in the background round the clock. Basically, we would like to have commands like: add-task *insert command here* list-tasks ...
4
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2answers
257 views

start process so that it can't spawn new ones

Is it possible to start new process so that it couldn't spawn new ones (untrusted code)? Also how do I start a process so it couldn't make any input/output to files and in general any devices?
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3answers
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How to kill two or more processes with one kill command?

I am using the following command to kill one java process via shell script: pidof java|xargs kill -9 $1 What if the list of pidof output has more than one elements? How do I kill them both with ...
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1answer
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How to know how long a process has been running? [duplicate]

Possible Duplicate: How to check how a long a program has been running? I am interested in doing this purely using bash.
4
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3k views

Slow down just one process to regulate CPU temperature

I have a program. When it is running, the CPU temperature raise from 50 to 80 Celcius, which is my major concern. I can control the CPU frequency to slow it down, but other processes will be slowed ...
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Measuring RAM usage of a program

time is a brilliant command if you want to figure out how much CPU time a given command takes. I am looking for something similar that can measure the max RAM usage of the program and any children. ...
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Alternatives for “lsof” command?

In many cases "lsof" is not installed on the machines that with I have to work, but the "function" of lsof would be needed very much (ex. on AIX). :\ Are there any "lsof" like applications in the ...