Use getopt() & getopt_long() to Parse Arguments

Today I came across a function [getopt] by accident.
It is very useful to parse command-line arguments with this tool!

Here is:

#inlcude <unistd.h>int getopt(int argc, char * const argv[], const char *optstring);extern char *optarg;extern int optind, opterr, optopt;#include <getopt.h>int getopt_long(int argc, char * const argv[], const char *optstring, const struct option *longopts, int *longindex);int getopt_long_only(int argc, char * const argv[], const char *optstring, const struct option *longopts, int *longindex);

---

Explain for getopt():

• Arguments argc and argv are the argument count and array as passed to the main() function.
• optstring is the options set. One semicolon following a character means that character need a argument, and two semicolon mean the argument is optional.
• optind is the index of the next element to be processed in argv. The system initializes this value to 1. You can reset it to 1 to restart scanning of the same argv, or when scanning a new argument vector.
• If there are no more option characters, getopt() returns -1 or, it will keep return the ASCII of the current character.
• optarg points to the argument string of one option if that option has argument following.

E.g.

#include <unistd.h>#include <stdio.h>#include <stdbool.h> // bool type/* Macro Definition */#define NO 0#define YES 1#define OK 0#define ERROR -1/* Structure for Global Arguments */struct GlbArgs_t{ bool version; bool help; char *number; char *type;}GlbArgs;/* Options allowed */static const char *optString = "n:t::vh?";/* Usage */static const char *usage = "Usage: \n" "-n\n" "-tx (x=type-name) \n" "-v\n" "-h -?\n";/* Initialize Global Argument structure */void InitGlbArg(){ GlbArgs.version = NO; GlbArgs.help = NO; GlbArgs.number = NULL; GlbArgs.type = NULL;}int main(int argc, char **argv){ int opt = 0; // option InitGlbArg(); while((opt = getopt(argc, argv, optString)) != ERROR){ switch(opt){ case 'n': GlbArgs.number = optarg; printf("Number: %s\n", GlbArgs.number); break; case 't': GlbArgs.type = optarg; printf("Type: %s\n", GlbArgs.type); break; case 'v': GlbArgs.version = YES; printf("Version: 1.0\n"); break; case 'h': case '?': printf("%s", usage); break; default: break; } } return OK;}

• Learn a lot from here
• For more details, refer to [man 3 getopt] (LInux)

Use getopt() & getopt_long() to Parse Arguments的更多相关文章

1. parse arguments in bash

   There are lots of ways to parse arguments in sh. Getopt is good. Here's a simple script that parses ...

2. 函数参数选项的处理getopt getopt_long getopt_long_only

   转载:http://blog.chinaunix.net/uid-20321537-id-1966849.html   在头文件中int getopt(int argc,char *argv[], c ...

3. C语言命令行解析函数：getopt/getopt_long

   命令行工具下的参数选项有两种,长选项和短选项.短选项以-开头,后面跟单个字母:长选项以--开头,后面可跟多个字母. 一. getopt() 1.功能:解析命令行短选项参数 2.函数原型: #inclu ...

4. 命令行解析函数：getopt/getopt_long

   参考: http://blog.csdn.net/zhangyang0402/article/details/5671410 http://www.cnblogs.com/gnuhpc/archive ...

5. getopt getopt_long

   getopt_long支持长选项的命令行解析,使用man getopt_long,得到其声明如下: #include <getopt.h> int getopt_long(int argc ...

6. 命令行参数解析：getopt&comma;getopt&lowbar;long

   #include <unistd.h> int getopt(int argc, char * const argv[], const char *optstring); extern c ...

7. getopt&lpar;&rpar; getopt&lowbar;long&lpar;&rpar;函数手册&lbrack;中文翻译&rsqb;

   getopt()函数 getopt_long函数 函数原型(function prototype) #include <unistd.h> int getopt(int argc, cha ...

8. apue编程之getopt &comma;getopt&lowbar;long使用方法以及实例

   1.getopt 1.1 函数定义 int getopt(int argc, char * const argv[], const char *optstring);#include <unis ...

9. 命令行解析函数：getopt&lowbar;long、getopt

   一.前言 在学习一些项目代码时,尤其涉及到命令行传参的代码,经常遇到getopt相关的函数,对这一类函数可以说是既陌生又熟悉.陌生是因为不知道它是干啥的,熟悉呢,是因为经常遇到.于是乎在追踪了多天ip ...

随机推荐

1. gridView使用

   只读 for (int i = 0; i <9; i++) { this.gridView1.Columns[i].OptionsColumn.ReadOnly = true; } 不显示面板 ...

2. 精通CSS&plus;DIV基础总结&lpar;一&rpar;

   这段时间学习了玩了DIV+CSS的视频,感觉效率不高.前边的Javascript总结的不好,但是看了后边的JQuery,觉得学习的再多一点,再进行Javascript的总结.DIV+CSS总结,估计会 ...

3. 【Leetcode】Same Tree

   给定两棵二叉树,判断是否相等(即树的结构以及各结点中的值都一样) Given two binary trees, write a function to check if they are equal ...

4. 使用JavaScript实现一个俄罗斯方块

   清明假期期间,闲的无聊,就做了一个小游戏玩玩,目前游戏逻辑上暂未发现bug,只不过样子稍微丑了一些-.-项目地址:https://github.com/Jiasm/tetris在线Demo:http: ...

5. vue中遇到的坑！！！！！

   一 .vue安装的坑 报错时的常见问题 1.cnpm install 模块名 –save-dev(关于环境的,表现为npm run dev 启动不了)cnpm install 模块名 –save(关于 ...

6. web&period;config&sol;app&period;config敏感数据加&sol;解密的二种方法

   一 建立虚拟目录  http://localhost/EncryptWebConfig,并添加web.config,其中包含数据库连接字符串: <connectionStrings>    ...

7. 第三节 java 数组

   一维数组: 同一种类型数据的集合,其实数组就是一个容器. 好处: 可以自动给数组中的元素从0开始编号,方便操作这些元素. 格式1: 元素类型[]  数组名 = new 元素类型 [元素个数或者元素长度 ...

8. tomcat部署成https协议

   1 生成密匙:进入jdk的bin目录后输入: keytool -genkeypair -alias "tomcat" -keyalg "RSA" -keysto ...

9. socket&comma;TCP&sol;IP的理解（转）

   TCP/IP 要想理解socket首先得熟悉一下TCP/IP协议族, TCP/IP(Transmission Control Protocol/Internet Protocol)即传输控制协议/网间 ...

10. CSS &colon; &commat;media 示例

    .example { padding: 20px; color: white; } /* Extra small devices (phones, 600px and down) */ @media ...