Reference
C Library
IOstream Library
Strings library
STL Containers
STL Algorithms
Miscellaneous
C Library
cassert (assert.h)
cctype (ctype.h)
cerrno (errno.h)
cfloat (float.h)
ciso646 (iso646.h)
climits (limits.h)
clocale (locale.h)
cmath (math.h)
csetjmp (setjmp.h)
csignal (signal.h)
cstdarg (stdarg.h)
cstddef (stddef.h)
cstdio (stdio.h)
cstdlib (stdlib.h)
cstring (string.h)
ctime (time.h)
cctype (ctype.h)
isalnum
isalpha
iscntrl
isdigit
isgraph
islower
isprint
ispunct
isspace
isupper
isxdigit
tolower
toupper


toupper

function
<cctype>
int toupper ( int c );

Convert lowercase letter to uppercase

Converts parameter c to its uppercase equivalent if c is a lowercase letter and has an uppercase equivalent. If no such conversion is possible, the value returned is c unchanged.

Notice that what is considered a letter may depend on the locale being used; In the default C locale, a lowercase letter is any of: a b c d e f g h i j k l m n o p q r s t u v w x y z, which translate respectively to: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z.

In C++, a locale-specific template version of this function (toupper) exists in header <locale>.

Parameters

c
Lowercase letter character to be converted, casted to an int, or EOF.

Return Value

The uppercase equivalent to c, if such value exists, or c (unchanged) otherwise. The value is returned as an int value that can be implicitly casted to char.

Example

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
/* toupper example */
#include <stdio.h>
#include <ctype.h>
int main ()
{
  int i=0;
  char str[]="Test String.\n";
  char c;
  while (str[i])
  {
    c=str[i];
    putchar (toupper(c));
    i++;
  }
  return 0;
}


Output:
TEST STRING.

See also