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TOUPPER(3)               BSD Library Functions Manual               TOUPPER(3)

NAME
     toupper, toupper_l -- lower case to upper case letter conversion

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <ctype.h>

     int
     toupper(int c);

     #include <ctype.h>
     #include <xlocale.h>

     int
     toupper_l(int c, locale_t loc);

DESCRIPTION
     The toupper() function converts a lower-case letter to the corresponding upper-case letter.  For single
     C chars locales (see multibyte(3)), the value of the argument is representable as an unsigned char or
     the value of EOF.

     Although the toupper() function uses the current locale, the toupper_l() function may be passed a
     locale directly. See xlocale(3) for more information.

RETURN VALUES
     If the argument is a lower-case letter, the toupper() function returns the corresponding upper-case
     letter if there is one; otherwise, the argument is returned unchanged.

COMPATIBILITY
     The 4.4BSD extension of accepting arguments outside of the range of the unsigned char type in locales
     with large character sets is considered obsolete and may not be supported in future releases.  The
     towupper() function should be used instead.

SEE ALSO
     ctype(3), isupper(3), multibyte(3), towupper(3), xlocale(3)

STANDARDS
     The toupper() function conforms to ISO/IEC 9899:1990 (``ISO C90'').

BSD                             August 21, 2004                            BSD