toupper
Synopsis
#include <ctype.h>
int toupper(int c);
Status
Implemented
Conformance
IEEE Std 1003.1-2017
Description
The toupper() function has as a domain a type int, the value of which is representable as a unsigned char or the
value of EOF.
If the argument has any other value, the behavior is undefined.
If the argument of toupper() represents a lowercase letter, and there exists a corresponding uppercase letter as
defined by character type information in the current locale respectively the result shall be the corresponding uppercase
letter.
All other arguments in the domain are returned unchanged.
Return value
Upon successful completion, the toupper() function shall return the uppercase letter corresponding to the argument
passed, otherwise, they shall return the argument unchanged.
Errors
No errors are defined.
Tests
Tested
Known bugs
None