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/* Strup.c - A function (and demonstration main) to convert a given
 * string to all upper case.  Notice the use of pointer notation when
 * working on a string a character at a time.  (A "for" loop could be
 * used instead.)
 *
 * Written 2001 by Wayne Pollock, Tampa Florida USA.
 */

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

void strup ( char string[] );

int main ( void )
{
   char buf[BUFSIZ];

   printf( "Please type a line of text: " );

   if ( fgets(buf, BUFSIZ, stdin) == NULL ) /* NULL is defined as 0 */
      return 1;

   /* buf usually has newline at end, unless the input is too long */
   printf("\n%-13s %s", "You Typed:", buf);

   strup(buf);

   printf("%-13s %s", "In uppercase:", buf);
   return 0;
}

/* Replaces the input (ASCII) string with an uppercase version of it */
void strup ( char s[] )
{
   int i = 0;
   while ( s[i] )  /* While not at the end of the string yet (marked by 0).  */
   {
      s[i] = toupper( s[i] );
      ++i;
   }
   return;
}

#ifdef COMMENTED_OUT /* Sample output of this program follows: */

Please type a line of text: Hello There on 10/30/98 (Friday)!

You typed:    Hello There on 10/30/98 (Friday)!
In uppercase: HELLO THERE ON 10/30/98 (FRIDAY)!

#endif