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

char *dir[64], *myargv[64];     // assume at most 64 parameters
char cmd [128];

int main(int argc, char *argv[], char *env[])
{
    int i, r;
    printf("THIS IS PROCESS %d IN %s\n", getpid( ), argv[0]);
    if(argc < 2){
        printf("Usage: a.out command [options]\n");
        exit(0);
    }
    printf("argc = %d\n", argc);
    for(i=0; i<argc; i++)       // print argv[ ] strings
        printf("argv[%d] = %s\n", i, argv[i]);

    for(i=0; i<argc-1; i++)     // create myargv[ ]
        myargv[i] = argv[i+1];
    myargv[i] = 0;              // NULL terminated array

    strcpy(cmd, "/bin/");       // create /bin/command
    strcat(cmd, myargv[0]);
    printf("cmd = %s\n", cmd);  // show filename to be executed
    int r = execve(cmd, myargv, env);
    // come to here only if execve( ) failed
    printf("execve( ) failed: r = %d\n", r);
}