SCANF(3W-SVR4)      RISC/os Reference Manual       SCANF(3W-SVR4)



NAME
     scanf, fscanf, sscanf - convert formatted input

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

     int scanf(const char *format [, pointer] ... );
     int fscanf(FILE *stream, const char *format [, pointer] ...
     );

     int sscanf(char *s, const char *format [, pointer] ... );

DESCRIPTION
     scanf() reads from the standard input stream stdin.
     fscanf() reads from the named input stream.  sscanf() reads
     from the character string s.  Each function reads characters
     (bytes), interprets them according to a control string for-
     mat, and stores the results in its arguments.

     The control string usually contains conversion specifica-
     tion, which are used to direct interpretation of input
     sequences.  The control string may contain:

          White-space characters (characters are defined in
          isspace() of ctype(3C)).  Except in two cases described
          below, these cause input to be read up to the next
          non-white-space character.

          An ordinary character (any EUC character , except the
          ASCII character %), which must match the next byte of
          the input stream.

          Conversion specifications which direct the conversion
          of the next input field.  Only ASCII characters are
          allowed as conversion characters.

     The conversion code indicates the interpretation of the
     input field, and the corresponding pointer argument must
     match the type being read.  wc and ws are the new conversion
     specifications for wchar_t character control, and both may
     be used in all three functions.

     wc   A wchar_t character is expected; the character, which
          should be in EUC, is transformed into a wchar_t charac-
          ter, and stored in the location pointed to by the
          corresponding argument which should be a wchar_t
          pointer.  The normal skip over white space is
          suppressed in this case.  To read the next non-space
          character as the wchar_t character, %1ws should be
          used.  If a field width is given, the corresponding
          argument should refer to a wchar_t array; the indicated
          number of wchar_t characters are read.



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SCANF(3W-SVR4)      RISC/os Reference Manual       SCANF(3W-SVR4)



     ws   A wchar_t string is expected; characters in EUC are
          transformed into wchar_t characters and stored in the
          location pointed to by the corresponding argument.  The
          corresponding argument should be a pointer pointing to
          a wchar_t array large enough to accept the string and a
          terminating wchar_t null character, which is added
          automatically.  wchar_t characters are read until the
          number of wchar_t characters specified in the field
          width, if supplied, or a white-space character is read.

     The conversion of these functions terminate at EOF or a NULL
     character in the case of sscanf(), at the end of the control
     string, or when an input character conflicts with the con-
     trol string.  In the last case, the offending character is
     left unread in the input stream.

     These functions return the number of successfully matched
     and assigned input items; this number can be zero in the
     event of an early conflict between an input character and
     the control string.  If the input ends before the first con-
     flict or conversion, EOF is returned.

WARNING
     A character from a supplementary code set in a scanset
     enclosed in a pair of square brackets is simply interpreted
     as a byte string.  Each byte of the input field is compared
     to the byte in the scanset.

SEE ALSO
     printf(3W), scanf(3S), stdio(3S), vprintf(3W), widec(3W).

























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