man pages section 3: Basic Library Functions

Exit Print View

Updated: July 2014
 
 

toupper(3C)

Name

toupper - transliterate lower-case characters to upper-case

Synopsis

#include <ctype.h> 

int toupper(int c);

Description

The toupper() function has as a domain a type int, the value of which is representable as an unsigned char or the value of EOF. If the argument has any other value, the argument is returned unchanged. If the argument of toupper() represents a lower-case letter, and there exists a corresponding upper-case letter (as defined by character type information in the program locale category LC_CTYPE), the result is the corresponding upper-case letter. All other arguments in the domain are returned unchanged.

Return Values

On successful completion, toupper() returns the upper-case letter corresponding to the argument passed.

Errors

No errors are defined.

Attributes

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE
ATTRIBUTE VALUE
CSI
Enabled
Interface Stability
Standard
MT-Level
MT-Safe

See Also

_toupper(3C), setlocale(3C), attributes(5), standards(5)