If I have multiple copies of the same application on the disk, and only one is running, as I can see with ps, how can I know the absolute path to distinguish it from the others?

% sudo ls -l /proc/PID/exe


% ps -auxwe | grep 24466
root     24466  0.0  0.0   1476   280 ?        S     2009   0:00 supervise sshd
% sudo ls -l /proc/24466/exe
lrwxrwxrwx 1 root root 0 Feb  1 18:05 /proc/24466/exe -> /package/admin/daemontools-0.76/command/supervise
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    In my system (ubuntu 14.04) you do not have to be superuser to run the ls command. – jarno Mar 5 '16 at 8:42
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    @jarno ls: cannot read symbolic link /proc/28783/exe: Permission denied -- it's not about running the ls command, it's about accessing the process info of a process not belonging to you. On my box, about 97% of all processes listed in /proc are root processes, and the others are distributed over 11 different users. – Irfy Mar 21 '16 at 12:53


pwdx $pid

This gives you the current working directory of the pid, not its absolute path.

Usually the which command will tell you which is being invoked from the shell:

#> which vlc
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    @Kokizzu No, it doesn't because it doesn't answer the question at all. The which command only tells you which binary will be run if you execute the command now. The question was "which binary is already running there". Imagine for example having a dozen jdks on your computer. If you want to know for a running java process which jdk it's been taken from, which doesn't help you with that. It will only tell you which jdk it will be taken from, if you execute it now. The accepted answer is also the correct one. – noamik Feb 18 '16 at 9:05
  • An obvious way this answer is wrong: on my machine I run processes with different JDK versions and some 32bits/64bits. If I want to identify the correct jstack/jmap version for the process the answer above will not work while the accepted answer will. – Daniel Da Cunha Dec 7 '16 at 7:36
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    @Kokizzu This only answers the question, "What is the current working directory of the process $pid?" The edited post still doesn't answer the question. which merely tells "If the command is on the path, then what is it?" – John Strood Jun 5 '18 at 11:42
  • pwdx return me the absolute path of the exectuable program of the process depending on pid on redhat x64 6.3. – Nick Dong Dec 30 '18 at 6:05
  • This does not answer the question at all. – Peter Mortensen Dec 30 '20 at 14:53

One way is ps -ef

  • 6
    didn't work for a specific service, it just provide the relative path – Jader Dias Feb 1 '10 at 16:57
  • Helped me identify a process via the command it was started with. – jpierson Feb 9 '16 at 18:50
  • this one can be executed on iOS – Blazej SLEBODA Dec 17 '20 at 10:28
ps auxwwwe



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    does not show ALL full qualified paths on my linux: "root 24466 0.0 0.0 1476 280 ? S 2009 0:00 supervise sshd " for example – akira Feb 1 '10 at 17:04
  • This is more accurate than the other answers... maybe not as useful, but more the right answer. Upvoted. – John Hunt Aug 30 '17 at 14:55
  • Can you add sample output and how to interpret it (for a self-contained answer)? Display of all environment variables makes for a lot of noise. E.g., is it the "_" variable that contains the answer? – Peter Mortensen Nov 20 '20 at 5:27

lsof is an option. You can try something like below:

lsof -p PROCESS_ID

This will list all the files opened by the process including the executable's actual location. It is then possible to add a few more awk, cut, grep etc. to find out the information that you are looking for.

As an example, I executed the following commands to identify where my 'java' process came from:

lsof -p 12345 | awk '{print $NF}' | grep 'java$'

The quick answer is to use ps with options or the /proc filesystem info. That will usually work, but is not guaranteed. In general, there is no definite, guaranteed answer. For instance, what if the executing file is deleted during execution, so that there is no path to the file?

See the Unix FAQ for a little more detail, particularly questions 4.3 and 4.4.


Why does everyone expect you to know the PID? Here's the human-friendly way:

pwdx `pgrep ###process_name###`
  • The question states “as I can see with ps”, so it will probably display the PID – Scz Apr 9 '17 at 13:24
  • Ah ok true. I still find this to be a quicker one liner in many of my use cases. – moodboom Apr 9 '17 at 15:41
  • This tells you the current working directory of the process, not the path to its executable. – David Moles Jan 14 at 20:08
  • Good point, they may be different. – moodboom Jan 15 at 15:56

You could use

readlink /proc/$(pgrep -x -U $(id -ur) APP_NAME)/exe


find /proc/$(pgrep -x -U $(id -ur) APP_NAME)/exe -printf "%l\n"

to get the absolute path of APP_NAME running as current user.

  • AFAICT this isn't using the PID at all and just errors out – electrovir Apr 21 '20 at 0:03
  • @electrovir fixed the description. – jarno Apr 21 '20 at 4:38

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