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diff --git a/3rdparty/petitfs-0.03/doc/pf/read.html b/3rdparty/petitfs-0.03/doc/pf/read.html new file mode 100644 index 00000000..a76c8ed3 --- /dev/null +++ b/3rdparty/petitfs-0.03/doc/pf/read.html @@ -0,0 +1,73 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> +<html lang="en"> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> +<meta http-equiv="Content-Style-Type" content="text/css"> +<link rel="up" title="Petit FatFs" href="../00index_p.html"> +<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default"> +<link rel="stylesheet" href="../css_p.css" type="text/css" media="screen" title="ELM Default"> +<title>Petit FatFs - pf_read</title> +</head> + +<body> + +<div class="para"> +<h2>pf_read</h2> +<p>The pf_read function reads data from the file.</p> +<pre> +FRESULT pf_read ( + void* <span class="arg">buff</span>, <span class="c">/* [OUT] Pointer to the read buffer */</span> + UINT <span class="arg">btr</span>, <span class="c">/* [IN] Number of bytes to read */</span> + UINT* <span class="arg">br</span> <span class="c">/* [OUT] Number of bytes read */</span> +); +</pre> +</div> + +<div class="para"> +<h4>Parameters</h4> +<dl class="par"> +<dt>buff</dt> +<dd>Pointer to the buffer to store the read data. A NULL specifies the destination is an outgoing stream.</dd> +<dt>btr</dt> +<dd>Number of bytes to read.</dd> +<dt>br</dt> +<dd>Pointer to the variable to return number of bytes read.</dd> +</dl> +</div> + + +<div class="para"> +<h4>Return Values</h4> +<dl class="ret"> +<dt>FR_OK (0)</dt> +<dd>The function succeeded.</dd> +<dt>FR_DISK_ERR</dt> +<dd>The function failed due to a hard error in the disk function, a wrong FAT structure or an internal error.</dd> +<dt>FR_NOT_OPENED</dt> +<dd>The file has not been opened.</dd> +<dt>FR_NOT_ENABLED</dt> +<dd>The volume has not been mounted.</dd> +</dl> +</div> + + +<div class="para"> +<h4>Description</h4> +<p>The file read/write pointer in the file system object advances in number of bytes read. After the function succeeded, <tt>*br</tt> should be checked to detect end of file. In case of <tt>*br < btr</tt>, it means the read pointer reached end of file during read operation.</p> +<p>If a NULL is given to the <tt class="arg">buff</tt>, the read bytes will be forwarded to the outgoing stream instead of the memory. The streaming function will be typically built-in the <tt>disk_readp()</tt> function.</p> +</div> + +<div class="para"> +<h4>QuickInfo</h4> +<p>Available when <tt>_USE_READ == 1</tt>.</p> +</div> + + +<div class="para"> +<h4>References</h4> +<p><tt><a href="open.html">pf_open</a>, <a href="write.html">pf_write</a>, <a href="sfatfs.html">FATFS</a></tt></p> +</div> + +<p class="foot"><a href="../00index_p.html">Return</a></p> +</body> +</html> |