environment variable access bench

#include <cassert>
#include <cstdlib>
#include <cstdio>
#include <ctime>
//#include <iostream>
#include <cstring>
//#include <string>

extern char ** environ;

const int LOOP=100000;

inline void loop1(char *buf, clock_t t, int a, int i) {
    t=clock();
    for(a=0;a<LOOP;++a) {
        for(i=0;environ[i]!=NULL;++i) {
            if(strncmp(environ[i],"PATH=",5)==0) buf=environ[i]+5;
        }
    }
    t=clock()-t;
    printf("%s\n", buf);
    printf ("%d clicks (%f seconds)\n", (int)t, ((float)t)/CLOCKS_PER_SEC);
}

inline void loop2(char *buf, clock_t t, int a, int i, char* envp[]) {
    t=clock();
    for(a=0;a<LOOP;++a) {
        for(i=0;envp[i]!=NULL;++i) {
            if(strncmp(envp[i],"PATH=",5)==0) buf=envp[i]+5;
        }
    }
    t=clock()-t;
    printf("%s\n", buf);
    printf ("%d clicks (%f seconds)\n", (int)t, ((float)t)/CLOCKS_PER_SEC);
}

inline void loop3(char *buf, clock_t t, int a) {
    t=clock();
    for(a=0;a<LOOP;++a) {
        buf=getenv("PATH");
    }
    t=clock()-t;
    printf("%s\n", buf);
    printf ("%d clicks (%f seconds)\n", (int)t, ((float)t)/CLOCKS_PER_SEC);
}

int main(int argc, char* argv[], char* envp[]) {
    char *buf=NULL;
    clock_t t=0;
    int a=0;
    int i=0;
    if(argc==2) {
        if( strcmp(argv[1],"-v")==0 || strcmp(argv[1],"--version")==0 ) {
            printf("%s version 0.0.1\n", argv[0]);
        }
        if(argv[1][1]=='\0') {
            if(argv[1][0]=='1') loop1(buf, t, a, i);
            if(argv[1][0]=='2') loop2(buf, t, a, i, envp);
            if(argv[1][0]=='3') loop3(buf, t, a);
        }
        return 1;
    }
    return 0;
}
//