toolchain/share/doc/gdb/read.html

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<h5 class="unnumberedsubsubsec">read</h5>
<p><a name="index-read_002c-file_002di_002fo-system-call-3606"></a>
<dl>
<dt>Synopsis:<dd>
<pre class="smallexample"> int read(int fd, void *buf, unsigned int count);
</pre>
<br><dt>Request:<dd>&lsquo;<samp><span class="samp">Fread,</span><var>fd</var><span class="samp">,</span><var>bufptr</var><span class="samp">,</span><var>count</var></samp>&rsquo;
<br><dt>Return value:<dd>On success, the number of bytes read is returned.
Zero indicates end of file. If count is zero, read
returns zero as well. On error, -1 is returned.
<br><dt>Errors:<dd>
<dl>
<dt><code>EBADF</code><dd><var>fd</var> is not a valid file descriptor or is not open for
reading.
<br><dt><code>EFAULT</code><dd><var>bufptr</var> is an invalid pointer value.
<br><dt><code>EINTR</code><dd>The call was interrupted by the user.
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