C ctype isupper() Function
Example
Check if a character is an uppercase letter:
char c = 'b';
if (isupper(c)) {
  printf("%c is an uppercase letter", c);
} else {
  printf("%c is not an uppercase letter", c);
}
Definition and Usage
The isupper() function returns a non-zero value (equivalent to boolean true) if 
a character is an uppercase letter.
The isupper() function is defined in the <ctype.h> header file.
Syntax
int isupper(int c);Parameter Values
| Parameter | Description | 
|---|---|
| c | Required. The ASCII value of a character or an actual character | 
Technical Details
| Returns: | An intvalue which is non-zero (equivalent to boolean true) if the character is an uppercase letter.Otherwise it returns 0 (equivalent to boolean false). | 
|---|
 
