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<H2><A NAME="SECTION00912000000000000000">8.1.2 Formatted Input</A></H2>
<A NAME="sec_formin"> </A>
<P>
Just as <B>printf(...)</B> is used for formatted output you can use
<B>scanf(...)</B> for formatted input.
<P>
<UL><LI> <TT>int fscanf(FILE *stream, const char *format, ...)</TT> <A NAME="fun_fscanf"> </A><BR>
<B>fscanf(...)</B> reads from <TT>stream</TT> and will transform the
input with the rules defined in <TT>format</TT>. The results will be
placed in the arguments given by <TT>...</TT>(<B>Note:</B> the arguments
<B>must</B> be pointer.). The read ends, when no more transformation
rules are in <TT>format</TT>. <B>fscanf(...)</B> will return EOF
when the first transformation reached the file end or some error
occured. Otherwise it will return the number of transformed arguments.
<P>
<TT>format</TT> can include rules on how to format the input arguments
(see table <A HREF="node88.html#tab_scanf">8.2</A> on page <A HREF="node88.html#tab_scanf"><IMG ALIGN=BOTTOM ALT="gif" SRC="/icons//cross_ref_motif.gif"></A>). It can also include:
<UL><LI> Spaces or tabs, which are ignored.<LI> any normal character (except %). The characters must be in the
input on the corresponding position.<LI> transformation rules, which assembled with a <I>%</I>, the
optional character <I>*</I> (this will permit <B>fscanf(...)</B>
to assign
to an argument), an optional number, an optional character
<I>h, l or L</I> (this is for the length of the target) and the
transformation character.
</UL><LI> <TT>int scanf(const char *format, ...)</TT> <A NAME="fun_scanf"> </A><BR>
The same as <B>fscanf(stdin,...)</B>.<LI> <TT>int sscanf(char *str, const char *format, ...)</TT> <A NAME="fun_sscanf"> </A><BR>
As <B>scanf(...)</B>, but the input comes from <TT>str</TT>.
</UL>
<P>
<P><A NAME="47836"> </A><A NAME="tab_scanf"> </A> <IMG WIDTH=472 HEIGHT=282 ALIGN=BOTTOM ALT="table47835" SRC="img8.gif" > <BR>
<STRONG>Table 8.2:</STRONG> Libc - scanf transformations<BR>
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<I>Converted on: <BR>
Fri Mar 29 14:43:04 EST 1996</I>
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