TOUPPER(3C) Standard C Library Functions TOUPPER(3C)
NAME
toupper, toupper_l - transliterate lower-case characters to upper-
case
SYNOPSIS
#include <ctype.h>
int toupper(
int c);
int toupper_l(
int c,
locale_t loc);
DESCRIPTION
The
toupper() function has as a domain of 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 locale category
LC_CTYPE), the
result is the corresponding upper-case letter. All other arguments in
the domain are returned unchanged.
The function
toupper_l() behaves identically to
toupper(), except
instead of operating in the current locale, it operates in the locale
specified by
loc.
A macro form,
_toupper() exists. It is defined for standards
conformance, particularly with legacy standards. It was deprecated in
POSIX 2008 (Issue 7), and its use is discouraged. The macro, on this
system, is just an alias for
toupper().
RETURN VALUES
On successful completion,
toupper() returns the upper-case letter
corresponding to the argument passed.
ERRORS
No errors are defined.
ATTRIBUTES
See
attributes(7) for descriptions of the following attributes:
+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|CSI | Enabled |
+--------------------+-----------------+
|Interface Stability | Standard |
+--------------------+-----------------+
|MT-Level | MT-Safe |
+--------------------+-----------------+
SEE ALSO
newlocale(3C),
setlocale(3C),
uselocale(3C),
attributes(7),
standards(7) October 4, 2015 TOUPPER(3C)
