ps xuwww -p PID

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <errno.h>

#include <libproc.h>

int main (int argc, char* argv[])

{

    pid_t pid; int ret;

    char pathbuf[PROC_PIDPATHINFO_MAXSIZE];

    if ( argc >  ) {

        pid = (pid_t) atoi(argv[]);

        ret = proc_pidpath (pid, pathbuf, sizeof(pathbuf));

        if ( ret <=  ) {

            fprintf(stderr, "PID %d: proc_pidpath ();\n", pid);

            fprintf(stderr, "    %s\n", strerror(errno));

        } else {

            printf("proc %d: %s\n", pid, pathbuf);

        }

    }

    return ;

}