Dynamically finding the path of C Binary which is invoking python

Well, the main thing you need to do is get the current working directory in your C script, and then you can either write some C code to combine the result with argv[0] to create the full path to the file and pass that to your python script as command line argument when you call it. Alternatively, you could pass both argv[0] and the result of getcwd() as parameters to your Python script, which is what I did below:

requestAudit.c

#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>

int main(int argc, const char* argv[]) {
    char* cwd = getcwd(NULL, 0);
    char* command = "python audit.py ";
    char* combine;

    // I added 2 because 1 for the null terminator and 1 for the space
    // between cwd and argv[0]
    size_t len = strlen(command) + strlen(cwd) + strlen(argv[0]) + 2;
    combine = malloc(sizeof(*combine)*len);
    strncpy(combine, command, strlen(command) + 1);
    strncat(combine, cwd, strlen(cwd) + 1);
    strncat(combine, " ", 2);
    strncat(combine, argv[0], strlen(argv[0]) + 1);
    return system(combine);
}

audit.py

import sys

if __name__ == "__main__":
    full_path = sys.argv[1] + sys.argv[2][1:]
    print(full_path)

This is just one way to do it, I'm sure there are other, probably better, ways to do this.