getopt对于不是以option方式给出的参数怎么获得

lpsir

int getopt(int argc, char * const argv[], const char *optstring);
optstring以：分隔的原则是什么
就像ｍａｎ里面while ((c = getopt(argc, argv, ":abf:")) != -1)

看不懂
哪位能解释一下　:abf:　的含义 　
九号　已解决
继续看ｍａｎ发现新的疑问　在四楼有描述
还请多多帮助

弥敦路九号

from beginning linux programming 3rd

To help us adhere to these guidelines, Linux gives us the getopt facility, which supports the use of
options with and without values and is simple to use.
#include <unistd.h>
int getopt(int argc, char *const argv[], const char *optstring);
extern char *optarg;
extern int optind, opterr, optopt;
The getopt function takes the argc and argv parameters as passed to the program’s main function and
an options specifier string that tells getopt what options are defined for the program and whether they
have associated values. The optstring is simply a list of characters, each representing a single character
option. If a character is followed by a colon, it indicates that the option has an associated value that will
be taken as the next argument. The getopts command in bash performs a very similar function.
For example, the following call would be used to handle our preceding example
getopt(argc, argv, “if:lr”);
It allows for simple options -i, -l , -r, and -f, followed by a filename argument. Calling the command
with the same parameters but in a different order will alter the behavior. Try it out when we get to the
sample code in the next “Try It Out” section in this chapter.

：表示指定的参数后面要求一个值，如：
xx -i -f filename -l -r
那个值可以用 optarg 取到。

btw,　要勾中"在文字中禁用表情符号"

lpsir

谢谢了
看了半天的ｍａｎ　
愣是没看懂

lpsir

就好像
cc -o sock sock.c
和
cc sock.c -o sock
都可以用一样
若是用getopt获得输入参数　对于sock.c这个参数是怎么获得的
看ｍａｎ似乎是　与optind 有点关系　　但是不明白
请解释一下

弥敦路九号

1. 
   
2. #include <stdio.h>
   
3. #include <unistd.h>
   
4. int main(int argc, char *argv[])
   
5. {
   
6. int opt;
   
7. while((opt = getopt(argc, argv, “if:lr”)) != -1) {
   
8. switch(opt) {
   
9. case ‘i’:
   
10. case ‘l’:
    
11. case ‘r’:
    
12. printf(“option: %c\n”, opt);
    
13. break;
    
14. case ‘f’:
    
15. printf(“filename: %s\n”, optarg);
    
16. break;
    
17. case ‘:’:
    
18. printf(“option needs a value\n”);
    
19. break;
    
20. case ‘?’:
    
21. printf(“unknown option: %c\n”, optopt);
    
22. break;
    
23. }
    
24. }
    
25. for(; optind < argc; optind++)
    
26. printf(“argument: %s\n”, argv[optind]);
    
27. exit(0);
    
28. }
    

复制代码

printf(“filename: %s\n”, optarg);

lpsir

谢谢
我的意思是那些不是以 -opt para
指出的parameter
ｍａｎ里面说
ｇｅｔｏｐｔ当遇到此类ｐａｒａｍｅｔｅｒ会返回－１
我也试验了
程序用getopt时　有限制
就是必须把有－ｏｐｔ　指定的参数写在前面
否则的话　若是在　－ｏｐｔ　之间出现不是有选项指定的参数
参数后面的　选项就失效了
假设　f:a:
a.out -f t1 -a t2 t3
这个时候t1 t2 t3都会按照设想的方式获得
a.out -f t1 t3 -a t2
但是这个时候就不会把-a t2认为是一个选项　因为ｇｅｔｏｐｔ在遇到　t3的时候就退出了