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diff --git a/www/c3ref/mprintf.html b/www/c3ref/mprintf.html new file mode 100644 index 0000000..002eadd --- /dev/null +++ b/www/c3ref/mprintf.html @@ -0,0 +1,170 @@ +<!DOCTYPE html> +<html><head> +<meta name="viewport" content="width=device-width, initial-scale=1.0"> +<meta http-equiv="content-type" content="text/html; charset=UTF-8"> +<link href="../sqlite.css" rel="stylesheet"> +<title>Formatted String Printing Functions</title> +<!-- path=../ --> +</head> +<body> +<div class=nosearch> +<a href="../index.html"> +<img class="logo" src="../images/sqlite370_banner.gif" alt="SQLite" border="0"> +</a> +<div><!-- IE hack to prevent disappearing logo --></div> +<div class="tagline desktoponly"> +Small. Fast. 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Both routines return a +NULL pointer if <a href="../c3ref/free.html">sqlite3_malloc64()</a> is unable to allocate enough +memory to hold the resulting string.</p> + +<p>The sqlite3_snprintf() routine is similar to "snprintf()" from +the standard C library. The result is written into the +buffer supplied as the second parameter whose size is given by +the first parameter. Note that the order of the +first two parameters is reversed from snprintf(). This is an +historical accident that cannot be fixed without breaking +backwards compatibility. Note also that sqlite3_snprintf() +returns a pointer to its buffer instead of the number of +characters actually written into the buffer. We admit that +the number of characters written would be a more useful return +value but we cannot change the implementation of sqlite3_snprintf() +now without breaking compatibility.</p> + +<p>As long as the buffer size is greater than zero, sqlite3_snprintf() +guarantees that the buffer is always zero-terminated. The first +parameter "n" is the total size of the buffer, including space for +the zero terminator. So the longest string that can be completely +written will be n-1 characters.</p> + +<p>The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().</p> + +<p>See also: <a href="../printf.html">built-in printf()</a>, <a href="../lang_corefunc.html#printf">printf() SQL function</a> +</p><p>See also lists of + <a href="../c3ref/objlist.html">Objects</a>, + <a href="../c3ref/constlist.html">Constants</a>, and + <a href="../c3ref/funclist.html">Functions</a>.</p> + |