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toupper(3p) — Linux manual page

PROLOG | NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLES | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT 

TOUPPER(3P)             POSIX Programmer's Manual            TOUPPER(3P)

PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The
       Linux implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior),
       or the interface may not be implemented on Linux.

NAME         top

       toupper, toupper_l — transliterate lowercase characters to
       uppercase

SYNOPSIS         top

       #include <ctype.h>

       int toupper(int c);
       int toupper_l(int c, locale_t locale);

DESCRIPTION         top

       For toupper(): The functionality described on this reference page
       is aligned with the ISO C standard. Any conflict between the
       requirements described here and the ISO C standard is
       unintentional. This volume of POSIX.1‐2017 defers to the ISO C
       standard.

       The toupper() and toupper_l() functions have 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
       behavior is undefined.

       If the argument of toupper() or toupper_l() represents a
       lowercase letter, and there exists a corresponding uppercase
       letter as defined by character type information in the current
       locale or in the locale represented by locale, respectively
       (category LC_CTYPE), the result shall be the corresponding
       uppercase letter.

       All other arguments in the domain are returned unchanged.

       The behavior is undefined if the locale argument to toupper_l()
       is the special locale object LC_GLOBAL_LOCALE or is not a valid
       locale object handle.

RETURN VALUE         top

       Upon successful completion, toupper() and toupper_l() shall
       return the uppercase letter corresponding to the argument passed;
       otherwise, they shall return the argument unchanged.

ERRORS         top

       No errors are defined.

       The following sections are informative.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       None.

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       setlocale(3p), uselocale(3p)

       The Base Definitions volume of POSIX.1‐2017, Chapter 7, Locale,
       ctype.h(0p), locale.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic
       form from IEEE Std 1003.1-2017, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The
       Open Group Base Specifications Issue 7, 2018 Edition, Copyright
       (C) 2018 by the Institute of Electrical and Electronics
       Engineers, Inc and The Open Group.  In the event of any
       discrepancy between this version and the original IEEE and The
       Open Group Standard, the original IEEE and The Open Group
       Standard is the referee document. The original Standard can be
       obtained online at http://www.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page
       are most likely to have been introduced during the conversion of
       the source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group               2017                       TOUPPER(3P)

Pages that refer to this page: ctype.h(0p),  sort(1p),  setlocale(3p),  _toupper(3p)

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