Linux C Programing - Arguments(2)

时间:2021-09-26 03:50:19
#include <iostream>
#include <stdlib.h>
#include <stdio.h> //printf
#include <unistd.h> //extern char **environ
using namespace std; #include <vector>
#define _GNU_SOURCE #include <getopt.h> // THIS PROGRAM CAN ./program --env=HOME
// ./program -e HOME
// ./program --e HOME
// ./program -h
// ./program --h or ./program --help
extern char **environ;
int main(int argc,char *argv[])
{
/*
cout << "Hello, World!" << endl;
char *v_char = "houdini";
char *v_char_list[5]={"jack","luke"}; cout << v_char<<endl;
cout << v_char_list[0]<<endl;
return 0;
*/ /*
char *v_char_list[] = {"jack","luke"};
char **v_char_point = v_char_list; while(v_char_point!=NULL)
{
cout<<*v_char_point<<endl;
v_char_point++;
}
*/ if (argc<=)
{
printf("THIS IS A LINUX TOOLS BASED ON KATANA,PLEASE -h/--help SHOW TIPS\n");
} int opt;
struct option longopts[] = {
{"env",,NULL,'e'},
{"help",,NULL,'h'},
{"showenv",,NULL,'s'},
{,,,}
};
while ((opt=getopt_long(argc,argv,":e:h:s",longopts,NULL)) != - )
{
switch (opt) {
case 'e':
{
printf("get new option: %s \n", optarg);
char *env_name = getenv(optarg);
if (env_name)
{
printf("%s value is %s \n", optarg, env_name);
}
else
{
printf("The %s env do not exist\n", env_name);
}
break;
}
case 'h':
{
printf("\033[40;37m -h/--help : This Program helps\n \033[0m");
printf("\033[40;37m -e=value/--env=value : You want get the env value\n \033[0m");
printf("\033[40;37m -s/--showenv : show current environment \n \033[0m");
printf("\n");
break;
}
case 's':
{
char **env=environ;
while(*env)
{
printf("%s\n",*env);
env++;
}
break;
}
case '?':
printf("unkown option: %c \n",optopt);
break;
}
};
for(;optind<argc;optind++)
{
printf(" \"%s\" argument have no use...: \n",argv[optind]);
} exit();
}