/**@author cody*@date 2014-08-12*@description *//*extern char **environ  //environment values#include <stdlib.h>char *getenv(const char *name);int setenv(const char *name,const char *value,int rewrite); // set enviroment if exists rewrite - 0 do  not rewrite not 0 rewritevoid unsetenv(const char *name); //delete env by name*/#include <stdio.h>#include <stdlib.h>void environment(){    extern char **environ;    int i;    for(i = 0;environ[i] != NULL;i ++){        printf("%s\n",environ[i] );    }}void getPath(){    char *path = getenv("PATH");    printf("PATH = %s\n",path );    setenv("PATH","HELLO",1);    path = getenv("PATH");    printf("PATH = %s\n",path );}int main(int argc, char const *argv[]){        //environment();    getPath();    return 0;}