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WSCANF(3)                  Library Functions Manual                  WSCANF(3)

NAME
     wscanf, fwscanf, swscanf, vwscanf, vswscanf, vfwscanf - wide character
     input format conversion

LIBRARY
     Standard C Library (libc, -lc)

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

     int
     wscanf(const wchar_t * restrict format, ...);

     int
     fwscanf(FILE * restrict stream, const wchar_t * restrict format, ...);

     int
     swscanf(const wchar_t * restrict str, const wchar_t * restrict format,
         ...);

     #include <stdarg.h>

     int
     vwscanf(const wchar_t * restrict format, va_list ap);

     int
     vswscanf(const wchar_t * restrict str, const wchar_t * restrict format,
         va_list ap);

     int
     vfwscanf(FILE * restrict stream, const wchar_t * restrict format,
         va_list ap);

DESCRIPTION
     The wscanf() family of functions scans input according to a format as
     described below.  This format may contain conversion specifiers; the
     results from such conversions, if any, are stored through the pointer
     arguments.  The wscanf() function reads input from the standard input
     stream stdin, fwscanf() reads input from the stream pointer stream, and
     swscanf() reads its input from the wide-character string pointed to by
     str.  The vfwscanf() function is analogous to vfwprintf(3) and reads
     input from the stream pointer stream using a variable argument list of
     pointers (see stdarg(3)).  The vwscanf() function scans a variable
     argument list from the standard input and the vswscanf() function scans
     it from a wide-character string; these are analogous to the vwprintf()
     and vswprintf() functions respectively.  Each successive pointer argument
     must correspond properly with each successive conversion specifier (but
     see the * conversion below).  All conversions are introduced by the %
     (percent sign) character.  The format string may also contain other
     characters.  White space (such as blanks, tabs, or newlines) in the
     format string match any amount of white space, including none, in the
     input.  Everything else matches only itself.  Scanning stops when an
     input character does not match such a format character.  Scanning also
     stops when an input conversion cannot be made (see below).

CONVERSIONS
     Following the % character introducing a conversion there may be a number
     of flag characters, as follows:

     *               Suppresses assignment.  The conversion that follows
                     occurs as usual, but no pointer is used; the result of
                     the conversion is simply discarded.

     hh              Indicates that the conversion will be one of dioux or n
                     and the next pointer is a pointer to a char (rather than
                     int).

     h               Indicates that the conversion will be one of dioux or n
                     and the next pointer is a pointer to a short int (rather
                     than int).

     l (ell)         Indicates that the conversion will be one of dioux or n
                     and the next pointer is a pointer to a long int (rather
                     than int), that the conversion will be one of a, e, f, or
                     g and the next pointer is a pointer to double (rather
                     than float), or that the conversion will be one of c or s
                     and the next pointer is a pointer to an array of wchar_t
                     (rather than char).

     ll (ell ell)    Indicates that the conversion will be one of dioux or n
                     and the next pointer is a pointer to a long long int
                     (rather than int).

     L               Indicates that the conversion will be one of a, e, f, or
                     g and the next pointer is a pointer to long double.

     j               Indicates that the conversion will be one of dioux or n
                     and the next pointer is a pointer to a intmax_t (rather
                     than int).

     t               Indicates that the conversion will be one of dioux or n
                     and the next pointer is a pointer to a ptrdiff_t (rather
                     than int).

     z               Indicates that the conversion will be one of dioux or n
                     and the next pointer is a pointer to a size_t (rather
                     than int).

     q               (deprecated.)  Indicates that the conversion will be one
                     of dioux or n and the next pointer is a pointer to a long
                     long int (rather than int).

     In addition to these flags, there may be an optional maximum field width,
     expressed as a decimal integer, between the % and the conversion.  If no
     width is given, a default of "infinity" is used (with one exception,
     below); otherwise at most this many characters are scanned in processing
     the conversion.  Before conversion begins, most conversions skip white
     space; this white space is not counted against the field width.

     The following conversions are available:

     %     Matches a literal `%'.  That is, "%%" in the format string matches
           a single input `%' character.  No conversion is done, and
           assignment does not occur.

     d     Matches an optionally signed decimal integer; the next pointer must
           be a pointer to int.

     i     Matches an optionally signed integer; the next pointer must be a
           pointer to int.  The integer is read in base 16 if it begins with
           `0x' or `0X', in base 8 if it begins with `0', and in base 10
           otherwise.  Only characters that correspond to the base are used.

     o     Matches an octal integer; the next pointer must be a pointer to
           unsigned int.

     u     Matches an optionally signed decimal integer; the next pointer must
           be a pointer to unsigned int.

     x, X  Matches an optionally signed hexadecimal integer; the next pointer
           must be a pointer to unsigned int.

     a, A, e, E, f, F, g, G
           Matches a floating-point number in the style of wcstod(3).  The
           next pointer must be a pointer to float (unless l or L is
           specified.)

     s     Matches a sequence of non-white-space wide characters; the next
           pointer must be a pointer to char, and the array must be large
           enough to accept the multibyte representation of all the sequence
           and the terminating NUL character.  The input string stops at white
           space or at the maximum field width, whichever occurs first.

           If an l qualifier is present, the next pointer must be a pointer to
           wchar_t, into which the input will be placed.

     S     The same as ls.

     c     Matches a sequence of width count wide characters (default 1); the
           next pointer must be a pointer to char, and there must be enough
           room for the multibyte representation of all the characters (no
           terminating NUL is added).  The usual skip of leading white space
           is suppressed.  To skip white space first, use an explicit space in
           the format.

           If an l qualifier is present, the next pointer must be a pointer to
           wchar_t, into which the input will be placed.

     C     The same as lc.

     [     Matches a nonempty sequence of characters from the specified set of
           accepted characters; the next pointer must be a pointer to char,
           and there must be enough room for the multibyte representation of
           all the characters in the string, plus a terminating NUL character.
           The usual skip of leading white space is suppressed.  The string is
           to be made up of characters in (or not in) a particular set; the
           set is defined by the characters between the open bracket [
           character and a close bracket ] character.  The set excludes those
           characters if the first character after the open bracket is a
           circumflex ^.  To include a close bracket in the set, make it the
           first character after the open bracket or the circumflex; any other
           position will end the set.  To include a hyphen in the set, make it
           the last character before the final close bracket; some
           implementations of wscanf() use "A-Z" to represent the range of
           characters between `A' and `Z'.  The string ends with the
           appearance of a character not in the (or, with a circumflex, in)
           set or when the field width runs out.

           If an l qualifier is present, the next pointer must be a pointer to
           wchar_t, into which the input will be placed.

     p     Matches a pointer value (as printed by `%p' in wprintf(3)); the
           next pointer must be a pointer to void.

     n     Nothing is expected; instead, the number of characters consumed
           thus far from the input is stored through the next pointer, which
           must be a pointer to int.  This is not a conversion, although it
           can be suppressed with the * flag.

     The decimal point character is defined in the program's locale (category
     LC_NUMERIC).

     For backwards compatibility, a "conversion" of `%\0' causes an immediate
     return of EOF.

RETURN VALUES
     These functions return the number of input items assigned, which can be
     fewer than provided for, or even zero, in the event of a matching
     failure.  Zero indicates that, while there was input available, no
     conversions were assigned; typically this is due to an invalid input
     character, such as an alphabetic character for a `%d' conversion.  The
     value EOF is returned if an input failure occurs before any conversion
     such as an end-of-file occurs.  If an error or end-of-file occurs after
     conversion has begun, the number of conversions which were successfully
     completed is returned.

SEE ALSO
     fgetwc(3), scanf(3), wcrtomb(3), wcstod(3), wcstol(3), wcstoul(3),
     wprintf(3)

STANDARDS
     The fwscanf(), wscanf(), swscanf(), vfwscanf(), vwscanf() and vswscanf()
     functions conform to ISO/IEC 9899:1999 ("ISO C99").

BUGS
     In addition to the bugs documented in scanf(3), wscanf() does not support
     the "A-Z" notation for specifying character ranges with the character
     class conversion (`%[').

NetBSD 10.99                     July 5, 2003                     NetBSD 10.99