toupper()                Convert 'c' to Uppercase, If Appropriate
 
 #include   <ctype.h>
 
 int        toupper(c);
 int        c;                           Character to be converted
 
    toupper() converts 'c' to uppercase if 'c' is a lowercase letter. If
    not, it remains unchanged.
 
    Returns:    The converted character 'c'.  There is no error return.
 
      Notes:    toupper() is a macro.  Since toupper() does not correctly
                handle 'c' arguments with side effects, the library
                contains a function version. The function version may be
                used if the definition of tolower() is removed using
                #undef, or if the header <ctype.h> is not included at
                all. The function tolower() is declared in <stdlib.h>.
 
  -------------------------------- Example ---------------------------------
 
    The following statements convert the characters in 'string' to
    uppercase before printing them out.
 
         #include <ctype.h>
         #include <stdio.h>
 
         char string[15] = "Alphabet Soup";
         int x;
 
         main()
         {
             for (x = 0; x < strlen(string); x++)
                 printf("%c",toupper(string[x]));
             printf("\n");
         }

Seealso:


 isupper() 
 islower() 
 _toupper()