btowc(3p) — Linux manual page

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

       btowc — single byte to wide character conversion

SYNOPSIS         top

       #include <stdio.h>
       #include <wchar.h>

       wint_t btowc(int c);

DESCRIPTION         top

       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 btowc() function shall determine whether c constitutes a valid
       (one-byte) character in the initial shift state.

       The behavior of this function shall be affected by the LC_CTYPE
       category of the current locale.

RETURN VALUE         top

       The btowc() function shall return WEOF if c has the value EOF or
       if (unsigned char) c does not constitute a valid (one-byte)
       character in the initial shift state. Otherwise, it shall return
       the wide-character representation of that character.

       In the POSIX locale, btowc() shall not return WEOF if c has a
       value in the range 0 to 255 inclusive.

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

       wctob(3p)

       The Base Definitions volume of POSIX.1‐2017, stdio.h(0p),
       wchar.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                         BTOWC(3P)

Pages that refer to this page: wchar.h(0p),  fwprintf(3p),  wctob(3p)

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