_TOUPPER(3) Library Functions Manual _TOUPPER(3)

_toupper — transliterate lowercase characters to uppercase


#include <ctype.h>

int _toupper(int c);

The _toupper () macro shall be equivalent to toupper(3) except that the application shall ensure that the argument is a lowercase letter.

Upon successful completion, _toupper () shall return the uppercase letter corresponding to the argument passed.

No errors are defined.

None.

Applications should use the toupper(3) function instead of the obsolescent _toupper () function.

None.

The _toupper () function may be removed in a future version.

islower(3) , toupper(3)

XBD V1_chap07(7) , <ctype.h>

First released in Issue 1. Derived from Issue 1 of the SVID.

The normative text is updated to avoid use of the term "must" for application requirements.

The _toupper () function is marked obsolescent.

January 1, 2008 posix.fail