In computing, the process identifier (normally referred to as the process ID or just PID) is a number used by most operating system kernels, —such as that of UNIX, Mac OS X or Microsoft Windows— to temporarily uniquely identify a process. This number may be used as a parameter in various function ...

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52 views

Write program output to log file containing PID in its name

How can I start a program and write its output to a log file, where the log file contains the PID in its name? I tried program_a > log_$! which doesn't work since $! is the PID of the last ...
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2answers
82 views

Writing own daemon. systemd error: Failed to read PID from file: Invalid argument

I'm trying to write own daemon a la very simple MPD (it's operating systems laboratory work). I made it work: it starts like a daemon (output of ps): 1 14877 14877 14877 ? -1 Ss 0 ...
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2answers
123 views

Why pidof and pgrep are behaving differently?

I have a init script in /etc/init.d/myservice for initialize a service like this: ... start() { ... daemon /usr/sbin/myservice ... } stop() { ... pgrep myservice pidof myservice ps -ef ...
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1answer
75 views

Find the PID's of all threads of a process without ps or pidof

So the system I'm working on (BusyBox) has a ps that takes no command line arguments and pidof returns nothing even though it exists within /sbin and points to killall5. Another issue I had is that ...
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1answer
57 views

How can I rejoin a process running

I am very new to using Linux. I have a 'machine' on Amazon and I was trying to learn how to use Python on this machine. I started running Python—had to step away for a few minutes and the connection ...
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1answer
91 views

How to get pid of su --session-command file thats ran on there [closed]

This line ran in a script su --session-command="$javaCommandLine & >>$serviceLogFile 2>&1 & echo \$! >$pidFile" $serviceUser || return 1 pid="$(<$pidFile)" echo $pid The ...
5
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2answers
192 views

Obtaining PID of command earlier in Pipeline

I'm writing a bash script to use inotifywait to monitor a directory and kick off actions when changes are detected. Something like: inotifywait -m ... | while read f; do something; done Since ...
2
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3answers
204 views

Why do top and ps show different PIDs for the same processes?

When I run top -H, I see that my multiple mysql threads all have the same PID. However, in ps -eLf I see each one has a different PID: ps -eLf UID PID PPID LWP C NLWP STIME TTY ...
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2answers
185 views

Get the PID of file creation

I am writing a bash script that creates 5 files with the extension ".P" and write a line of "something" into them. "P" represents a number and it's the PID of the process that creates the file. How ...
21
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3answers
932 views

If computers start counting at 0, why does the init process have a pid of 1?

Not much to put here in the body, the question is self explanatory.
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3answers
66 views

ssh targetHost &; fg - does not work, but why?

I was trying the following combination in order to get the pid of the ssh session (running in the background displays the pid) and than fg to get back to the ssh session and introduce the password: ...
5
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1answer
134 views

How to monitor top applications using CPU (and IO if possible) in a graph?

I need to find what and when these applications used so much CPU (and IO if possible too). This should be in a graphic timeline like we see in GNOME System Monitor CPU History. I also want to compare ...
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1answer
148 views

Startscript: using $! to create pidfile - returning wrong pid (off by one) occasionally

We have 3 instances of redis running on a test server. For some reason, our start script which starts redis can write the wrong pid to a file. Here is what it's doing: su redis -c "redis-server ...
3
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1answer
821 views

bash: Run command in background and capture pid [duplicate]

Am writing a bash 4.1 script... Would like run another script (or internal function) in the background... And capture the pid of that background job in a variable in the foreground script... If the ...
2
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5answers
502 views

Get return value of process by PID

If I have the PID of a process that was killed, how might I get the return status of the process? I am particularly interested to know if the return status was 143 (kill) or 137 (kill -9) as I don't ...
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1answer
316 views

How does One Find the PID of a Process Started with startproc?

My understanding is that it's generally a good idea to create a PID file for daemon processes and that startproc is a good way to start these daemons. I know that startproc takes -i and -p arguments ...
3
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2answers
175 views

How to monitor the last PID assigned by the kernel?

To monitor process creation I'd like to periodically write the last PID assigned by the kernel to any process on the system (not just processes created by the PID-monitoring program) with a time stamp ...