btowc(3) — Linux manual page

btowc(3)                 Library Functions Manual                btowc(3)

NAME         top

       btowc - convert single byte to wide character

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <wchar.h>

       wint_t btowc(int c);

DESCRIPTION         top

       The btowc() function converts c, interpreted as a multibyte
       sequence of length 1, starting in the initial shift state, to a
       wide character and returns it.  If c is EOF or not a valid
       multibyte sequence of length 1, the btowc() function returns WEOF.

RETURN VALUE         top

       The btowc() function returns the wide character converted from the
       single byte c.  If c is EOF or not a valid multibyte sequence of
       length 1, it returns WEOF.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                            │ Attribute     │ Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │ btowc()                              │ Thread safety │ MT-Safe │
       └──────────────────────────────────────┴───────────────┴─────────┘

STANDARDS         top

       C11, POSIX.1-2008.

HISTORY         top

       C99, POSIX.1-2001.

NOTES         top

       The behavior of btowc() depends on the LC_CTYPE category of the
       current locale.

       This function should never be used.  It does not work for
       encodings which have state, and unnecessarily treats single bytes
       differently from multibyte sequences.  Use either mbtowc(3) or the
       thread-safe mbrtowc(3) instead.

SEE ALSO         top

       mbrtowc(3), mbtowc(3), wctob(3)

COLOPHON         top

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Linux man-pages 6.15            2025-05-17                       btowc(3)

Pages that refer to this page: wctob(3),  wprintf(3)

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