环境变量地址获取

posix

#include 
#include 

extern char **environ;

int main(int argc, char *argv[])
{
        char **p = environ;

        while (*p != NULL)
        {
                printf("%s (%p)\n", *p, *p);
                *p++;
        }

        return 0;
}

most system also support

#include 

int main(int argc, char *argv[], char *envp[])
{
        char **p = envp;

        while (*p != NULL)
        {
                printf("%s (%p)\n", *p, *p);
                *p++;
        }

        return 0;
}