干点小事的常用的着的语句

//int main(int argc,const char *argv[],const char **env[])
int main(int argc,char **argv)
{
    //help usage;argc-程序的参数counter,argument arg-counter,arg-value;
    if(argc<3){
        printf("Usage:%s old_name new_name\n",argv[0]);
        return;
    }

    //printf("%s\n",argv[1]);

    //printf("%s=%s\n",argc[1],argv[2]);//参数第二个
    if(rename(argv[1],argv[2])<0)
        printf("error!\n");
    else
        printf("ok!\n");
}