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FatFs R0.13a, released October 14, 2017

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This commit is contained in:
Christopher Williams
2017-11-11 23:43:22 -07:00
parent 5c7915feab
commit 7ee1f4cc87
61 changed files with 1240 additions and 779 deletions
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documents/doc/printf.html
+18 -13
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@@ -1,7 +1,7 @@
<!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-Type" content="text/html; charset=utf-8">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/printf.html">
@@ -29,7 +29,7 @@ int f_printf (
<dt>fp</dt>
<dd>Pointer to the open file object structure.</dd>
<dt>fmt</dt>
<dd>Pointer to the null terminated format string. The terminator charactor will not be written.</dd>
<dd>Pointer to the null <tt>'\0'</tt> terminated format string. The terminator character will not be output.</dd>
<dt>...</dt>
<dd>Optional arguments...</dd>
@@ -39,25 +39,28 @@ int f_printf (
<div class="para ret">
<h4>Return Values</h4>
<p>When the function succeeded, it returns number of characters written. If the function could not write the generated string to the file due to disk full or an error, <tt>EOF (-1)</tt> will be returned.</p>
<p>When the string was written successfuly, it returns number of character encoding units written to the file. When the function failed due to disk full or any error, an <tt>EOF (-1)</tt> will be returned.</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The format control directive is a sub-set of standard library shown as follos:</p>
<ul>
<li>Type: <tt>c C s S d D u U x X b B</tt></li>
<li>Size: <tt>l L</tt></li>
<li>Flag: <tt>0 -</tt></li>
</ul>
<p>The format control directive is a sub-set of standard library shown as follows:</p>
<pre>
%[flag][width][type]
</pre>
<dl>
<dt>flag</dt><dd>Padding options. A <tt>-</tt> specifies left justified. A <tt>0</tt> specifies zero padded.</dd>
<dt>width</dt><dd>Minimum width of the field, <tt>1-99</tt> or <tt>*</tt>. If the width of generated string is less than the specified value, rest field is padded with white spaces or zeros. An <tt>*</tt> specifies the value comes from an argument in int type.</dd>
<dt>type</dt><dd><tt>c s d u o x b</tt> and prefix <tt>l</tt> specify type of the argument, character, string, signed integer in decimal, unsigned integer in decimal, unsigned integer in octal, unsigned integer in hexdecimal and unsigned integer in binary respectively. If <tt>sizeof (long)</tt> is greater than <tt>sizeof (int)</tt> (this is typical of 8/16-bit systems), a prefix <tt>l</tt> needs to be explicitly specified for long integer argument. These characters except for <tt>x</tt> are case insensitive.</dd>
</dl>
<p>When FatFs is configured for Unicode API (<tt><a href="config.html#lfn_unicode">FF_LFN_UNICODE</a> &gt;= 1</tt>), character encoding on the string fuctions, <tt>f_putc</tt>, <tt>f_puts</tt>, <tt>f_printf</tt> and <tt>f_gets</tt> function, is also switched to Unicode. The Unicode characters in multiple encoding unit, such as surrogate pair and multi-byte sequence, should not be divided into two function calls, or the character will be lost. The character encoding <em>on the file</em> to be written via this function is selected by <tt><a href="config.html#strf_encode">FF_STRF_ENCODE</a></tt> option. If the character encoding on the file differs from that on the API, it is converted in this function. In this case, input characters with wrong encoding or invalid for the output will be lost.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>This is a wrapper function of <a href="write.html"><tt>f_write</tt></a> function. Available when <tt>FF_FS_READONLY == 0</tt> and <tt>FF_USE_STRFUNC</tt> is 1 or 2. When it is set to 2, <tt>'\n'</tt>s contained in the output are converted to <tt>'\r'+'\n'</tt>.</p>
<p>When FatFs is configured to Unicode API (<tt>FF_LFN_UNICODE == 1</tt>), data types on the srting fuctions, <tt>f_putc</tt>, <tt>f_puts</tt>, <tt>f_printf</tt> and <tt>f_gets</tt> function, is also switched to Unicode. The character encoding on the file to be read/written via those functions is selected by <tt>FF_STRF_ENCODE</tt> option.</p>
<p>This is a wrapper function of <a href="write.html"><tt>f_write</tt></a> function. Available when <tt><a href="config.html#fs_readonly">FF_FS_READONLY</a> == 0</tt> and <tt><a href="config.html#use_strfunc">FF_USE_STRFUNC</a> &gt;= 1</tt>. When it is set to 2, <tt>'\n'</tt>s contained in the output are converted to <tt>'\r'+'\n'</tt> each.</p>
</div>
@@ -69,16 +72,18 @@ int f_printf (
<em>f_printf</em>(&amp;fil, "%ld", 12345L); <span class="c">/* "12345" */</span>
<em>f_printf</em>(&amp;fil, "%06d", 25); <span class="c">/* "000025" */</span>
<em>f_printf</em>(&amp;fil, "%06d", -25); <span class="c">/* "000-25" */</span>
<em>f_printf</em>(&amp;fil, "%*d", 5, 100); <span class="c">/* " 100" */</span>
<em>f_printf</em>(&amp;fil, "%-6d", 25); <span class="c">/* "25 " */</span>
<em>f_printf</em>(&amp;fil, "%u", -1); <span class="c">/* "65535" or "4294967295" */</span>
<em>f_printf</em>(&amp;fil, "%04x", 0xAB3); <span class="c">/* "0ab3" */</span>
<em>f_printf</em>(&amp;fil, "%08LX", 0x123ABCL); <span class="c">/* "00123ABC" */</span>
<em>f_printf</em>(&amp;fil, "%08lX", 0x123ABCL); <span class="c">/* "00123ABC" */</span>
<em>f_printf</em>(&amp;fil, "%04o", 255); <span class="c">/* "0377" */</span>
<em>f_printf</em>(&amp;fil, "%016b", 0x550F); <span class="c">/* "0101010100001111" */</span>
<em>f_printf</em>(&amp;fil, "%s", "String"); <span class="c">/* "String" */</span>
<em>f_printf</em>(&amp;fil, "%8s", "abc"); <span class="c">/* " abc" */</span>
<em>f_printf</em>(&amp;fil, "%-8s", "abc"); <span class="c">/* "abc " */</span>
<em>f_printf</em>(&amp;fil, "%c", 'a'); <span class="c">/* "a" */</span>
<em>f_printf</em>(&amp;fil, "%f", 10.0); <span class="c">/* <em>f_printf</em> lacks floating point support */</span>
<em>f_printf</em>(&amp;fil, "%f", 10.0); <span class="c">/* f_printf lacks floating point support */</span>
</pre>
</div>