TOWCTRANS(3)               POSIX Programmer's Manual              TOWCTRANS(3)



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

NAME
       towctrans, towctrans_l -- wide-character transliteration

SYNOPSIS
       #include <wctype.h>

       wint_t towctrans(wint_t wc, wctrans_t desc);
       wint_t towctrans_l(wint_t wc, wctrans_t desc,
           locale_t locale);

DESCRIPTION
       For towctrans(): 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 towctrans() and towctrans___l() functions shall transliterate the
       wide-character code wc using the mapping described by desc.

       The current setting of the LC__CTYPE category in the current locale or
       in the locale represented by locale, respectively, should be the same
       as during the call to wctrans() or wctrans___l() that returned the value
       desc.

       If the value of desc is invalid (that is, not obtained by a call to
       wctrans() or desc is invalidated by a subsequent call to setlocale()
       that has affected category LC__CTYPE), the result is unspecified.

       If the value of desc is invalid (that is, not obtained by a call to
       wctrans___l() with the same locale object locale) the result is
       unspecified.

       An application wishing to check for error situations should set errno
       to 0 before calling towctrans() or towctrans___l().

       If errno is non-zero on return, an error has occurred.

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

RETURN VALUE
       If successful, the towctrans() and towctrans___l() functions shall return
       the mapped value of wc using the mapping described by desc.  Otherwise,
       they shall return wc unchanged.

ERRORS
       These functions may fail if:

       EINVAL desc contains an invalid transliteration descriptor.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       The strings "tolower" and "toupper" are reserved for the standard
       mapping names. In the table below, the functions in the left column are
       equivalent to the functions in the right column.


           towlower(wc)            towctrans(wc, wctrans("tolower"))
           towlower_l(wc, locale)  towctrans_l(wc, wctrans("tolower"), locale)
           towupper(wc)            towctrans(wc, wctrans("toupper"))
           towupper_l(wc, locale)  towctrans_l(wc, wctrans("toupper"), locale)

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       towlower(), towupper(), wctrans()

       The Base Definitions volume of POSIX.1-2017, <wctype.h>

COPYRIGHT
       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                         TOWCTRANS(3)
