How to get the PID of a process by giving the proc

问题:

I am writing a script to monitor the CPU and MEM of any given process. For that i need to send in the name of the process to be monitored as a commandline argument. For example.

./monitorscript <pname>

I need to get the pid of the process in the script so that i can use a ps -p <pid> inside.

How do i get the pid of a process given its process name?

I understand that there might be multiple processes in the same name. I just want to get the first process out of that list.

回答1:

The answer above was mostly correct, just needed some tweaking for the different parameters in Mac OSX.

ps -A | grep -m1 firefox | awk '{print $1}'

回答2:

You can install pidof with Homebrew:

brew install pidof
pidof <process_name>

回答3:

You can use the pgrep command like in the following example

$ pgrep Keychain\ Access
44186

回答4:

This is the shortest command I could find that does the job:

ps -ax | awk '/[t]he_app_name/{print $1}'

Putting brackets around the first letter stops awk from finding the awk process itself.

回答5:

Try this one:

echo "$(ps -ceo pid=,comm= | awk '/firefox/ { print $1; exit }')"

The ps command produces output like this, with the PID in the first column and the executable name (only) in the second column:

bookworm% ps -ceo pid=,comm=
    1 launchd
   10 kextd
   11 UserEventAgent
   12 mDNSResponder
   13 opendirectoryd
   14 notifyd
   15 configd

...which awk processes, printing the first column (pid) and exiting after the first match.

回答6:

This solution matches the process name more strictly:

ps -Ac -o pid,comm | awk '/^ *[0-9]+ Dropbox$/ {print $1}'

This solution has the following advantages:

• it ignores command line arguments like tail -f ~/Dropbox
• it ignores processes inside a directory like ~/Dropbox/foo.sh
• it ignores processes with names like ~/DropboxUID.sh

回答7:

You can try this

pid=$(ps -o pid=,comm= | grep -m1 $procname | cut -d' ' -f1)

回答8:

Why don't you run TOP and use the options to sort by other metrics, other than PID? Like, highest used PID from the CPU/MEM?

top -o cpu <---sorts all processes by CPU Usage