_tolower(3p) — Linux manual page

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

       _tolower — transliterate uppercase characters to lowercase

SYNOPSIS         top

       #include <ctype.h>

       int _tolower(int c);

DESCRIPTION         top

       The _tolower() macro shall be equivalent to tolower(c) except that
       the application shall ensure that the argument c is an uppercase
       letter.

RETURN VALUE         top

       Upon successful completion, _tolower() shall return the lowercase
       letter corresponding to the argument passed.

ERRORS         top

       No errors are defined.

       The following sections are informative.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       Applications should use the tolower() function instead of the
       obsolescent _tolower() function.

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

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

SEE ALSO         top

       tolower(3p), isupper(3p)

       The Base Definitions volume of POSIX.1‐2017, Chapter 7, Locale,
       ctype.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                      _TOLOWER(3P)

Pages that refer to this page: ctype.h(0p)

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