Remove upper case letters from a char string

I am very new to C, so please bear with me.

I have written the following function...

Code:

const char *RemoveUpper(unsigned char *text)
{
        int i = 0, len = strlen(text);
        static unsigned char new_str[4096];
        while (len > 0)
        {
                if (*text == toupper(*text)) {
                   new_str[i] = *text;
                }
                i++;
                text++;
                len--;
        }
        new_str[i] = 0;
        return new_str;
}

It is supposed to loop through every character of the variable text and check to see if it is upper case, by comparing it with the uppercase equivialant of it.

It seems to only return a single character.

What am I doing wrong here?

Thanks

~Phil~

Originally Posted by lavinpj1

It seems to only return a single character.

What am I doing wrong here?

What are you passing as input to the function?

Originally Posted by lavinpj1

It is supposed to loop through every character of the variable text and check to see if it is upper case, by comparing it with the uppercase equivialant of it.

Then a better name for the function would be helpfull, RemoveUpper seems to indicate a different purpose.

Code:

Then a better name for the function would be helpfull, RemoveUpper seems to indicate a different purpose.

It loops through every character in the input and check if it is uppercase. If it isn't, then it sticks the character to the end of a new char variable, therefore removing upper case letters.

What I think you may have been confused with is, if (*text == toupper(*text)) {. It is supposed to be if (*text != toupper(*text)) {. My mistake.

This is part of a module for unreal ircd. It is passed like this...

Code:

		
strncpyzt(retbuf, RemoveUpper(text), sizeof(retbuf));

in order to set retbuf = to the string inputted, but with the caps removed.

Cheers

Phil

Originally Posted by lavinpj1

It loops through every character in the input and check if it is uppercase. If it isn't, then it sticks the character to the end of a new char variable, therefore removing upper case letters.

Is this what you are saying?

Code:

#include <stdio.h>
#include <ctype.h>

char *RemoveUpper(const char *text)
{
   static char new_str[4096];
   int i = 0;
   for ( ; *text; ++text )
   {
      if ( !isupper(*text) )
      {
         new_str[i++] = *text;
      }
   }
   new_str[i] = 0;
   return new_str;
}

int main(void)
{
   char text[] = "Hello World";
   puts(text);
   puts(RemoveUpper(text));
   return 0;
}

/* my output
Hello World
ello orld
*/

Ah, thanks very much Dave.

That worked great, but what I did want as islower, not isupper. The only problem I am having, is, that like all programming languages, it thinks characters are uppercase. This is what I want, although I do not want to remove spaces. How would I go about stopping it removing spaces?

EDIT: Tried...

Code:

if ( ( islower(*text) ) && ( *text != ' ' ) )
      {
         new_str[i++] = *text;
      }

with no luck.

Cheers

~Phil~

Originally Posted by lavinpj1

The only problem I am having, is, that like all programming languages, it thinks characters are uppercase.

Originally Posted by lavinpj1

This is what I want, although I do not want to remove spaces. How would I go about stopping it removing spaces?

You want to keep only lowercase or spaces?

Code:

#include <stdio.h>
#include <ctype.h>

char *RemoveUpper(const char *text)
{
   static char new_str[4096];
   int i = 0;
   for ( ; *text; ++text )
   {
      if ( islower(*text) || isspace(*text) )
      {
         new_str[i++] = *text;
      }
   }
   new_str[i] = 0;
   return new_str;
}

int main(void)
{
   char text[] = "The Quick Brown Fox Jumps Over The Lazy Dog.";
   puts(text);
   puts(RemoveUpper(text));
   return 0;
}

/* my output
The Quick Brown Fox Jumps Over The Lazy Dog.
he uick rown ox umps ver he azy og
*/

Perfect! Thanks so much Dave. I would quite like a list of these string functions if you have one, as there are some real nice ones.

Cheers

~Phil~

http://www.cppreference.com/stdstring/index.html
http://www-ccs.ucsd.edu/c/ctype.html
http://www.dinkumware.com/manuals/re.../&h=ctype.html

Bookmarked!

Thanks again