# getopt.h是GNU标准库中头文件，主要功能提取命令行参数用于基于文本的C/C++程序。
# 工作目的：由于getopt.h并不为ANSIC标准库的一部分，在利用VS2015编程过程中需要使用其头文件。
查阅相关资料，整理如下：
# 拷贝头文件getopt.h
/***************************************************************************** * * MODULE NAME : GETOPT.C * * COPYRIGHTS: * This module contains code made available by IBM * Corporation on an AS IS basis. Any one receiving the * module is considered to be licensed under IBM copyrights * to use the IBM-provided source code in any way he or she * deems fit, including copying it, compiling it, modifying * it, and redistributing it, with or without * modifications. No license under any IBM patents or * patent applications is to be implied from this copyright * license. * * A user of the module should understand that IBM cannot * provide technical support for the module and will not be * responsible for any consequences of use of the program. * * Any notices, including this one, are not to be removed * from the module without the prior written consent of * IBM. * * AUTHOR: Original author: * G. R. Blair (BOBBLAIR at AUSVM1) * Internet: bobblair@bobblair.austin.ibm.com * * Extensively revised by: * John Q. Walker II, Ph.D. (JOHHQ at RALVM6) * Internet: johnq@ralvm6.vnet.ibm.com * *****************************************************************************/ /****************************************************************************** * getopt() * * The getopt() function is a command line parser. It returns the next * option character in argv that matches an option character in opstring. * * The argv argument points to an array of argc+1 elements containing argc * pointers to character strings followed by a null pointer. * * The opstring argument points to a string of option characters; if an * option character is followed by a colon, the option is expected to have * an argument that may or may not be separated from it by white space. * The external variable optarg is set to point to the start of the option * argument on return from getopt(). * * The getopt() function places in optind the argv index of the next argument * to be processed. The system initializes the external variable optind to * 1 before the first call to getopt(). * * When all options have been processed (that is, up to the first nonoption * argument), getopt() returns EOF. The special option "--" may be used to * delimit the end of the options; EOF will be returned, and "--" will be * skipped. * * The getopt() function returns a question mark (?) when it encounters an * option character not included in opstring. This error message can be * disabled by setting opterr to zero. Otherwise, it returns the option * character that was detected. * * If the special option "--" is detected, or all options have been * processed, EOF is returned. * * Options are marked by either a minus sign (-) or a slash (/). * * No errors are defined. *****************************************************************************/ #include <stdio.h> /* for EOF */ #include <string.h> /* for strchr() */ /* static (global) variables that are specified as exported by getopt() */ char *optarg = NULL; /* pointer to the start of the option argument */ int optind = 1; /* number of the next argv[] to be evaluated */ int opterr = 1; /* non-zero if a question mark should be returned when a non-valid option character is detected */ /* handle possible future character set concerns by putting this in a macro */ #define _next_char(string) (char)(*(string+1)) int getopt(int argc, char *argv[], char *opstring) { static char *pIndexPosition = NULL; /* place inside current argv string */ char *pArgString = NULL; /* where to start from next */ char *pOptString; /* the string in our program */ if (pIndexPosition != NULL) { /* we last left off inside an argv string */ if (*(++pIndexPosition)) { /* there is more to come in the most recent argv */ pArgString = pIndexPosition; } } if (pArgString == NULL) { /* we didn't leave off in the middle of an argv string */ if (optind >= argc) { /* more command-line arguments than the argument count */ pIndexPosition = NULL; /* not in the middle of anything */ return EOF; /* used up all command-line arguments */ } /*--------------------------------------------------------------------- * If the next argv[] is not an option, there can be no more options. *-------------------------------------------------------------------*/ pArgString = argv[optind++]; /* set this to the next argument ptr */ if (('/' != *pArgString) && /* doesn't start with a slash or a dash? */ ('-' != *pArgString)) { --optind; /* point to current arg once we're done */ optarg = NULL; /* no argument follows the option */ pIndexPosition = NULL; /* not in the middle of anything */ return EOF; /* used up all the command-line flags */ } /* check for special end-of-flags markers */ if ((strcmp(pArgString, "-") == 0) || (strcmp(pArgString, "--") == 0)) { optarg = NULL; /* no argument follows the option */ pIndexPosition = NULL; /* not in the middle of anything */ return EOF; /* encountered the special flag */ } pArgString++; /* look past the / or - */ } if (':' == *pArgString) { /* is it a colon? */ /*--------------------------------------------------------------------- * Rare case: if opterr is non-zero, return a question mark; * otherwise, just return the colon we're on. *-------------------------------------------------------------------*/ return (opterr ? (int)'?' : (int)':'); } else if ((pOptString = strchr(opstring, *pArgString)) == 0) { /*--------------------------------------------------------------------- * The letter on the command-line wasn't any good. *-------------------------------------------------------------------*/ optarg = NULL; /* no argument follows the option */ pIndexPosition = NULL; /* not in the middle of anything */ return (opterr ? (int)'?' : (int)*pArgString); } else { /*--------------------------------------------------------------------- * The letter on the command-line matches one we expect to see *-------------------------------------------------------------------*/ if (':' == _next_char(pOptString)) { /* is the next letter a colon? */ /* It is a colon. Look for an argument string. */ if (' ' != _next_char(pArgString)) { /* argument in this argv? */ optarg = &pArgString[1]; /* Yes, it is */ } else { /*------------------------------------------------------------- * The argument string must be in the next argv. * But, what if there is none (bad input from the user)? * In that case, return the letter, and optarg as NULL. *-----------------------------------------------------------*/ if (optind < argc) optarg = argv[optind++]; else { optarg = NULL; return (opterr ? (int)'?' : (int)*pArgString); } } pIndexPosition = NULL; /* not in the middle of anything */ } else { /* it's not a colon, so just return the letter */ optarg = NULL; /* no argument follows the option */ pIndexPosition = pArgString; /* point to the letter we're on */ } return (int)*pArgString; /* return the letter that matched */ } }
拷贝后的头文件放入工程目录下，并在主程序中包含 #include "getopt.h"。
另：拷贝相关头文件及其库函数可参考博客。
#getopt函数介绍：
（1）函数定义
int getopt(int argc, char *argv[], char *opstring)
（2）短参数定义
- 不带值的参数，定义本身即是参数。
- 必带值的参数，定义在参数后加冒号:。
- 可选值的参数，定义在参数后加两个冒号::。
（3） 参数介绍
- argc 接收main( )传递参数个数
- argv 接收main( )传递参数内容
- optstring 欲处理选项字符串作为短参数列表。
#用例说明：
主要内容参考博客链接
若oprstring收集短参数列表表示为"acd:e::"
ac表示不带参数，其本身即为参数。d必须定义参数，e可定义参数。
调用过程中，'-a -c -d dup -e'，'-a -c -d up -eeup','-ac -d dup -eeup'均为合法调用。
- 不带值的参数，可以连写或分开写。例如'-a -c'或'-ac'或'-ca'。
- 参数不区分先后顺序。
- 重点注意，可选值的参数值与参数之间不允许有空格，必须连写。例如'-eeup'
#返回值说明
- getopt( ) 逐次调用命令行参数。
- 直至所有参数遍历一遍，传入空参数getopt( )返回-1。
- 若发生不在optstring( )里面的参数，或必选值参数不带值时，返回"-1"。
#更为详细说明参考博客
- https://www.cnblogs.com/qingergege/p/5914218.html
- http://blog.51cto.com/vopit/440453
- https://www.cnblogs.com/oloroso/p/4856104.html
#windows窗口下调用
按照如上规则，编译后调用命令行窗口调用即可例如：
test.exe -ac -d dup -eeup