LinuxQuestions.org - [SOLVED] [C++] How to fetch the process id of the currently active C++ file?

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[C++] How to fetch the process id of the currently active C++ file?

I tried this:

Code:

#include <iostream>

#include <stdlib.h>

#include <sstream>



int main ()

{

    std::stringstream psOutput;

    psOutput << "ps --no-headers -f -p " << getpid();



    system (psOutput.str().c_str());



    return 0;

}

The output:

Code:

anisha@linux-trra:~/> ps -f

UID        PID  PPID  C STIME TTY          TIME CMD

anisha    6426  6423  0 13:32 pts/0    00:00:00 /bin/bash

anisha    7590  6426  0 15:32 pts/0    00:00:12 kwrite api.cpp

anisha    8099  6426  0 16:02 pts/0    00:00:00 ps -f



anisha@linux-trra:~/> g++ api.cpp -Wall

anisha@linux-trra:~/> ./a.out 

anisha    8119  6426  0 16:03 pts/0    00:00:00 ./a.out



anisha@linux-trra:~/>

I wanted the pid of api.cpp, not of a.out.

How to solve this?

a cpp files is not runnable, it is not a process. It will be compiled, and linked together with other compiled files and the result will be one single program. if you execute this process it will get a process id. In a multithreaded environment all the running threads will get also an id, but a source file (like your cpp) will never have a process id.

Quote:

Originally Posted by pan64 (Post 4888953)

but a source file (like your cpp) will never have a process id.

Thanks! What I was seeing was actually the pid of kwrite, not
of that cpp file!

I actually wanted to fetch the file name and was thinking of
extracting it from output of ps! :doh:

The simpler way is __FILE__! :)
http://gcc.gnu.org/onlinedocs/cpp/St...ed-Macros.html