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a problem about difference between GNU/Linux and Windows

This is from my .ini parser:

PHP Code:


		
			
      // check if this is a session line (e.g., [SECTION])

      if (str[0] == '[' && str[length - 1] == ']') {

         strcpy(section, &str[1]);

         section[length - 2] = 0; // remove the ]

This works in Windows, but in GNU/Linux I have to use:

PHP Code:


		
			
      // check if this is a session line (e.g., [SECTION])

      if (str[0] == '[' && str[length - 2] == ']') {

         strcpy(section, &str[1]);

         section[length - 3] = 0; // remove the ]

The problem is, why does the GNU/Linux has to use a different way ? Also I'm using gcc 3.4.2 for both of the OS's

I have also pre-processed the string read from the .ini file with this function:

PHP Code:


		
			
void trim(char *str)

{

   int pos = 0;

   char *dest = str;



   // skip leading blanks

   while (str[pos] == ' ' || str[pos] == '\t' || str[pos] == '\n')

      pos++;



   while (str[pos]) {

      *dest++ = str[pos];

      pos++;

   }



   *dest = '\0'; // store the null



   int i = strlen(str) - 1;

   while (i > 0 && (str[i] == ' ' || str[i] == '\t' || str[i] == '\n')) { // remove trailing blanks

      str[i--] = '\0';

   }

}

Re: a problem about difference between GNU/Linux and Windows

I think I know where is your problem
imagine you have text file made under windows, so end line is CR+LF. And now you will load this .ini file into your parser in windows and linux :

WINDOWS :
if you call fgets, it will detect newline as CR+LF and end character in your string is \n
You will use [length - 2] and everything is allright

LINUX :
if you call fgets, it reads until LF and string will have \r\n in the end. So you must use [length -3] to skip to section name

How to fix it :
I use something like this in my parser to skip trailing whitespaces

Code:

#include <string>



int main()

{

        std::string line = "    test string   \r\t\n  \r  \t\n  ";

        std::string result;



        std::string::size_type j;

        std::string::size_type begin = 0;

        std::string::size_type end = line.size();



        // skip all leading whitespaces

        for (j = begin; j < line.size(); ++j) {

                if (line[j] > ' ') 

                        break; 

                ++begin;

        }

        // skip all trailing whitespaces

        for (j = end; j > 0; --j) {

                if (line[j - 1] > ' ') 

                        break; 

                --end;

        }



        if (end > begin)

                result = line.substr (begin, end - begin);

        else

                result = " ";

}

However this code is for std::string class, not evil char array :)

You only check for \n in your trim function. You should also check for \r, or better, check for all whitespace characters by comparing them with space, like I did in previous example

more info : http://en.wikipedia.org/wiki/Newline