man-pages/man3/fgetc.3.html
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<H1>FGETC</H1>
Section: Linux Programmer's Manual (3)<BR>Updated: 2017-09-15<BR><A HREF="#index">Index</A>
<A HREF="/cgi-bin/man/man2html">Return to Main Contents</A><HR>
<A NAME="lbAB">&nbsp;</A>
<H2>NAME</H2>
fgetc, fgets, getc, getchar, ungetc - input of characters and strings
<A NAME="lbAC">&nbsp;</A>
<H2>SYNOPSIS</H2>
<PRE>
<B>#include &lt;<A HREF="file:///usr/include/stdio.h">stdio.h</A>&gt;</B>
<B>int fgetc(FILE *</B><I>stream</I><B>);</B>
<B>char *fgets(char *</B><I>s</I><B>, int </B><I>size</I><B>, FILE *</B><I>stream</I><B>);</B>
<B>int getc(FILE *</B><I>stream</I><B>);</B>
<B>int getchar(void);</B>
<B>int ungetc(int </B><I>c</I><B>, FILE *</B><I>stream</I><B>);</B>
</PRE>
<A NAME="lbAD">&nbsp;</A>
<H2>DESCRIPTION</H2>
<B>fgetc</B>()
reads the next character from
<I>stream</I>
and returns it as an
<I>unsigned char</I>
cast to an
<I>int</I>,
or
<B>EOF</B>
on end of file or error.
<P>
<B>getc</B>()
is equivalent to
<B>fgetc</B>()
except that it may be implemented as a macro which evaluates
<I>stream</I>
more than once.
<P>
<B>getchar</B>()
is equivalent to
<B>getc(</B><I>stdin</I><B>)</B><I></I>.
<P>
<B>fgets</B>()
reads in at most one less than
<I>size</I>
characters from
<I>stream</I>
and stores them into the buffer pointed to by
<I>s</I>.
Reading stops after an
<B>EOF</B>
or a newline.
If a newline is read, it is stored into the buffer.
A terminating null byte ('\0')
is stored after the last character in the buffer.
<P>
<B>ungetc</B>()
pushes
<I>c</I>
back to
<I>stream</I>,
cast to
<I>unsigned char</I>,
where it is available for subsequent read operations.
Pushed-back characters
will be returned in reverse order; only one pushback is guaranteed.
<P>
Calls to the functions described here can be mixed with each other and with
calls to other input functions from the
<I>stdio</I>
library for the same input stream.
<P>
For nonlocking counterparts, see
<B><A HREF="/cgi-bin/man/man2html?3+unlocked_stdio">unlocked_stdio</A></B>(3).
<A NAME="lbAE">&nbsp;</A>
<H2>RETURN VALUE</H2>
<B>fgetc</B>(),
<B>getc</B>()
and
<B>getchar</B>()
return the character read as an
<I>unsigned char</I>
cast to an
<I>int</I>
or
<B>EOF</B>
on end of file or error.
<P>
<B>fgets</B>()
returns
<I>s</I>
on success, and NULL
on error or when end of file occurs while no characters have been read.
<P>
<B>ungetc</B>()
returns
<I>c</I>
on success, or
<B>EOF</B>
on error.
<A NAME="lbAF">&nbsp;</A>
<H2>ATTRIBUTES</H2>
For an explanation of the terms used in this section, see
<B><A HREF="/cgi-bin/man/man2html?7+attributes">attributes</A></B>(7).
<TABLE BORDER>
<TR VALIGN=top><TD><B>Interface</B></TD><TD><B>Attribute</B></TD><TD><B>Value</B><BR></TD></TR>
<TR VALIGN=top><TD>
<B>fgetc</B>(),
<B>fgets</B>(),
<B>getc</B>(),
<BR>
<B>getchar</B>(),
<B>ungetc</B>()
</TD><TD>Thread safety</TD><TD>MT-Safe<BR></TD></TR>
</TABLE>
<P>
<A NAME="lbAG">&nbsp;</A>
<H2>CONFORMING TO</H2>
POSIX.1-2001, POSIX.1-2008, C89, C99.
<P>
It is not advisable to mix calls to input functions from the
<I>stdio</I>
library with low-level calls to
<B><A HREF="/cgi-bin/man/man2html?2+read">read</A></B>(2)
for the file descriptor associated with the input stream; the results
will be undefined and very probably not what you want.
<A NAME="lbAH">&nbsp;</A>
<H2>SEE ALSO</H2>
<B><A HREF="/cgi-bin/man/man2html?2+read">read</A></B>(2),
<B><A HREF="/cgi-bin/man/man2html?2+write">write</A></B>(2),
<B><A HREF="/cgi-bin/man/man2html?3+ferror">ferror</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?3+fgetwc">fgetwc</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?3+fgetws">fgetws</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?3+fopen">fopen</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?3+fread">fread</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?3+fseek">fseek</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?3+getline">getline</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?3+gets">gets</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?3+getwchar">getwchar</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?3+puts">puts</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?3+scanf">scanf</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?3+ungetwc">ungetwc</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?3+unlocked_stdio">unlocked_stdio</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?7+feature_test_macros">feature_test_macros</A></B>(7)
<A NAME="lbAI">&nbsp;</A>
<H2>COLOPHON</H2>
This page is part of release 5.05 of the Linux
<I>man-pages</I>
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
<A HREF="https://www.kernel.org/doc/man-pages/.">https://www.kernel.org/doc/man-pages/.</A>
<P>
<HR>
<A NAME="index">&nbsp;</A><H2>Index</H2>
<DL>
<DT id="1"><A HREF="#lbAB">NAME</A><DD>
<DT id="2"><A HREF="#lbAC">SYNOPSIS</A><DD>
<DT id="3"><A HREF="#lbAD">DESCRIPTION</A><DD>
<DT id="4"><A HREF="#lbAE">RETURN VALUE</A><DD>
<DT id="5"><A HREF="#lbAF">ATTRIBUTES</A><DD>
<DT id="6"><A HREF="#lbAG">CONFORMING TO</A><DD>
<DT id="7"><A HREF="#lbAH">SEE ALSO</A><DD>
<DT id="8"><A HREF="#lbAI">COLOPHON</A><DD>
</DL>
<HR>
This document was created by
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Time: 00:05:42 GMT, March 31, 2021
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