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

learn more… | top users | synonyms (1)

1
vote
1answer
29 views

How to use pgrep inside bash script correctly?

I'm running a GUI program called zeal(compiled from src) and add a script(zeal.sh) for the executable: #!/bin/bash if pgrep zeal &>/dev/null; then printf "already on\n" else ...
0
votes
2answers
93 views

The program pstree and htop showing threads with unique PIDS. How is this possible?

I ran the program pstree -p 31872 which printed the following output: ruby(31872)─┬─{ruby}(31906) └─{ruby}(32372) The man page for pstree says: Child threads of a process ...
1
vote
1answer
25 views

Remove Gnome Components detect by Packagename

I have tried out the dpkg, aptitude and apt commands. On the gnome desktop I decided to remove one component. sudo apt-get remove gnome-games or something else, all works fine. But if I don’t ...
3
votes
3answers
67 views

How to view a specific process in top

Are there any relatively strightforward options with top to track a specific process? Ideally by identifying the process by a human readable value? e.g. chrome or java. In other words, I want to view ...
1
vote
0answers
39 views

monitor a process by matching the full cmdline

I'm looking for a software that can monitor a process (specified as a partial string/regexp match (e.g. grepping) in its full command-line) in terms of cpu and memory usage. If any of those processes ...
9
votes
2answers
173 views

Print pids and names of processes as they are created

From the question here, the OP wants to repeatedly poll the pid of a process using pidof in a shell script. Of course this is inefficient as a new process must be started for the pidof program ...
1
vote
0answers
79 views

Are there any alternatives to pidof? (smaller footprint)

Well, I've just found out that with extensive usage of pidof in very short intervals, the seemingly tiny tool can be a great CPU hog. (Source: top) On my older machine, it can easily reach 30 percent ...
2
votes
2answers
244 views

set packet rate limit via iptables

I have a packet rate limit (max. 10 per seconds) which is set by my internet provider. This is a problem if I want to use the AceStream player, because if I exceed the limit I get disconnected. How ...
7
votes
4answers
490 views

How to find source of spawning process?

I have a Java process running on a RedHat Linux instance. The problem is it keeps reappearing after I kill it. I am not sure where to look. I've already went to crontab, but no luck. I've looked at ...
1
vote
1answer
31 views

What is the meaning of every column when executing psig command?

I try to use psig command to track signal dispositions of a process on Solaris: bash-3.2# psig 3109 3109: bash HUP caught termsig_sighandler 0 ...
3
votes
1answer
40 views

How to find the file corresponding to a pipe opened by a process? [duplicate]

I created this script, which listens for characters received on a hardcoded pipe, and tries to eval those characters. I call my script loop_executor.sh This is all it contains: !/bin/bash while : do ...
4
votes
3answers
131 views

How to get whole command line from a process?

How can I get the command arguments or the whole command line from a running process using its process name? For example this process: # ps PID USER TIME COMMAND 1452 root 0:00 ...
2
votes
1answer
34 views

How do I find the resident memory size of a process on busybox?

I run top on busybox and it shows all processes and their virtual memory size. How do I determine how much RAM is being used by each process?
3
votes
0answers
63 views

Kill a whole process tree regardless different GIDs

I am having issues with process control using the signals available to the process abstraction. In the example below you can see there is a perl script which is the parent of the whole tree with a ...
1
vote
1answer
46 views

Types of sleep modes for processes

I came across this while troubleshooting why our server is doing down everytime the oracle process is killed. I listed the oracle process running on the server using ps aux | grep oracle and here is ...
3
votes
1answer
74 views

Why does the 'user' and 'sys' time vary on multiple executions?

There is a nice question and answer explaining the relationships between 'real', 'user' and 'sys'. It explains the reasons why 'real' can vary, and defines the 'user' and 'sys' as times the process ...
2
votes
1answer
99 views

How to change the kernel max PID number? [duplicate]

The default PID max number is 32768. To get this information type: cat /proc/sys/kernel/pid_max 32768 or sysctl kernel.pid_max kernel.pid_max = 32768 Now, I want to change this number... but I ...
2
votes
2answers
55 views

How can I make a for loop starting a lot of processes?

I want to test some bug, and to do that I need to have a situation where the PID is larger than 99999. I am thinking of a bash script, a for loop. Any ideas?
6
votes
1answer
301 views

Is there a way to see if process listening on TCP port receives a message?

According to tcpdump, my server receives the following TCP packet: 12:52:29.603233 00:19:e2:9e:df:f0 00:16:3e:6a:25:3f, ethertype IPv4 (0x0800), length 74: 10.10.10.65.38869 192.168.215.82.22: ...
0
votes
2answers
66 views

What determines if an executable can be run in different independent processes simultaneously?

I posted a question about how to run an executable (a PDF viewer) under wine independently in multiple processes (independent means no communication between them, it is not parallel computing). I ...
0
votes
1answer
72 views

Kill unresponsive process by name but preserve responsive processes

For some reason, I end up with a fair few Google Chrome Helper processes which stop responding, hogging CPU resources. Usually I just run killall Google\ Chrome\ Helper, however this kills all, ...
2
votes
0answers
57 views

Why do some processes pass on their cpu usage to another process when it ends?

I have wondered this for a while. For example, lets say process1 is a process that uses a lot of cpu power, like 90%. Its a video game. Then i have process2 which uses 10-12% cpu. Its a web browser. ...
2
votes
1answer
39 views

w command for the other network hosts

While the who command refers to the local machine, rwho shows the same informations about all the known hosts of the local network. Similarly, w shows informations about the users on the local ...
0
votes
2answers
58 views

How to trick an application to run different processes?

I am running PDFXCview.exe (for pdfxchange viewer portable version) under wine to open a pdf file, by PDFXCview.exe 1.pdf When I do the same for another file, the other file will be opened by the ...
24
votes
3answers
1k views

How can I see the exact command line being executed inside some bash instance?

I have a long running bash instance (inside a screen session) that is executing a complex set of commands inside a loop (with each loop doing pipes, redirects, etc). The long command line was ...
31
votes
4answers
2k views

Is there any UNIX variant on which a child process dies with its parent?

I have been studying the Linux kernel behaviour for quite some time now, and it's always been clear to me that: When a process dies, all its children are given back to the init process (PID 1) ...
1
vote
2answers
73 views

How to get a procesess's actual memory usage (including data in swap)

I'm trying to check how much memory strain a process is actually putting on the system, but ps, top and friends are almost useless for that purpose as they only report 3 statistics: RES - the ...
2
votes
3answers
2k views

Cron job to check if PHP script is running, if not then run

I am wondering if someone might point me in the right direction. I've got little experience working with the Linux command line and recently due to various factors in work I've been required to gain ...
7
votes
1answer
237 views

What's the purpose of the /proc/pid/mountinfo file?

What's the purpose of the /proc/pid/mountinfo file (with pid being numerical process id)? As far as I can see it reflects contents of the /proc/mounts file but with added information. Also the file ...
3
votes
2answers
204 views

Kill a process that keeps restarting

What if 'kill -9' does not work? or How to kill a script which starts new processes? doesn't help me in anyway. I have a python script which starts automatically with another process id using ...
0
votes
0answers
14 views

Terminal output from a program not opened in terminal [duplicate]

Using bash on Ubuntu, I can launch programs from command line and watch what the program is doing 'in the background' while I use the GUI frontend. This is particularly handy when a GUI progress bar ...
0
votes
1answer
29 views

Using $BASHPID in grep statement

I'm trying to exclude the PID of the subshell from the results returned by pgrep. Note that the name of the file is the same as the name passed to pgrep. Why does setting a variable equal to BASHPID ...
1
vote
1answer
40 views

How can I determine what individual ulimit constraint a process has?

I have a service that sets a custom limit for open files (ulimit -n 5000) as part of its init script. My understanding is that this will be effectively for the service and its child processes. Since ...
8
votes
2answers
316 views

How can I tell when a process has finished writing to a file?

I have a process which has been spawned from a shell. It is running as a background process and exporting a DB to a CSV file in /tmp. How can I tell when the background process has completed ...
0
votes
1answer
56 views

What are the potential negatives of turning on process accounting (psacct package)?

I am looking into turning on process accounting on some EL6 servers. What are the potential pitfalls of turning this on? If you mitigate storage requirements with log rotation, any reason you would ...
1
vote
2answers
41 views

If I use one of the exec family functions to open a child process, will pipes to parent be applied to the child?

Say I open a parent process with a master process that assigns the stdout to a file for logging. Then say I use the parent process to open a child with execvp (or any other of the exec family of ...
4
votes
0answers
86 views

Strange cpu usage values reported by pidstat

I have a script that reports the cpu usage of a specific program reading values from pidstat. The script launches as: pidstat -C ^frontend$ -h -l -p ALL 1 1 The values reported this way sometimes ...
1
vote
3answers
86 views

Run linux process at very very low priority?

I have regular process that not so important but will consume so much CPU power, and I have another process which is really important, but it spend most of the time idle, but when it got a job it ...
0
votes
1answer
29 views

Background Process not running?

I ran a C program with an infinite while loop in a terminal and observed one of the CPU cores shot to 100% usage. When I turn it into a background process using Ctrl+z, the CPU usage suddenly dipped ...
2
votes
0answers
57 views

How to run the dialog command with proccess? [duplicate]

NOTE: Please look at my code, it's a Bash script. I want to display both dialogs on the screen at the same time, one dialog displays this: tail –f from - /var/log/proccess1.log and the second ...
2
votes
3answers
38 views

how to run the dialog command with proccess

Please look on my code – ( bash script ) I want to display both dialogs on the screen on the same time, one dialog display the: tail –f from - /var/log/proccess1.log , and the second dialog ...
1
vote
1answer
51 views

Deterministic method to find out whether some other process is in a chroot jail and where?

NOTE: I'm familiar with this U&L Q&A titled: How do I tell I'm running in a chroot? that sounds similar to what I'm asking, but there's a subtle difference to what I'm looking for. That ...
4
votes
1answer
54 views

How can process doing “vfork without exec” end up in a long uninterruptible sleep?

In this answer user suggests that Normally, Uninterruptible sleep should not last long, but as under windows, broken drivers or broken userpace programs (vfork without exec) can end up sleeping ...
1
vote
1answer
33 views

Empty kernel processes on CentOS vps : 2 different servers

I'm not sure I'm asking correctly, or perhaps I'm just looking at the wrong things. I'm migrating from one CentOS Vps (on an OpenVZ box) to another CentOS VPS (on a VMWare box). VPS #1 = CentOS ...
4
votes
1answer
84 views

How to completely detach a process

I want to spawn a process and run it at the top level so that when the shell exits, the process keeps running. I had mistakenly thought that nohup would do this, but when I exit from the shell (the ...
5
votes
2answers
407 views

Why does process substitution result in a file called /dev/fd/63 which is a pipe?

I am trying to understand named pipes in the context of this particular example. I type <(ls -l) in my terminal and get the output as, bash: /dev/fd/63: Permission denied. If I type cat <(ls ...
5
votes
1answer
117 views

Is the Unix process scheduler itself a process?

Is the Unix process scheduler itself a process, or does it piggyback on other processes in the same way a system call does (running kernel code in the user process with the kernel bit set)?
0
votes
1answer
54 views

Comparing Windows and Linux machine hardware

I have to compare Linux and Windows machine hardware? In windows system, I can open the My computer properties and see the details like processors, RAM Hard disks etc. Through task manager, I can see ...
9
votes
1answer
220 views

Why does the location of Enviroment Variables vary that much?

Reading the book Hacking: The Art of Exploitation by Jon Erickson, I am trying to approximate the address of an environment variable SHELLCODE to exploit a program. Every time I run ...
0
votes
2answers
51 views

Process auto starts itself not by cron

My linux server was hacked. and now there is a file in root directory that generates big traffic. when i kill this process it autostarts itself again. then i did chmod -x. but it returned x option. ...