Click above to get retro games delivered to your door ever month!

   tolower, toupper

   Usage
   #include <ctype.h>
   int tolower(int c);
   int toupper(int c);

   Description
   tolower  converts  any integer value c in the range of `A'  -  `Z'  to
   lower case.

   toupper  converts  any integer value c in the range of `a'  -  `z'  to
   upper case.

   These  are implemented as macros in ctype.h, and are also included  as
   functions within the library. Undefining the macros, or not  including
   ctype.h, will cause the library functions to be used.

   Example
   #include <ctype.h>
   #include <stdio.h>
   main()
   {
        printf("Lowercase character [%c]\n",tolower(0x4d));
   }

   Return Value
   tolower  returns  c,  converted to lower case if it  was  upper  case,
   otherwise c is returned unchanged.

   toupper  returns  c,  converted to upper case if it  was  lower  case,
   otherwise c is returned unchanged.