| <html lang="en"> |
| <head> |
| <title>Non-reentrant Conversion - The GNU C Library</title> |
| <meta http-equiv="Content-Type" content="text/html"> |
| <meta name="description" content="The GNU C Library"> |
| <meta name="generator" content="makeinfo 4.13"> |
| <link title="Top" rel="start" href="index.html#Top"> |
| <link rel="up" href="Character-Set-Handling.html#Character-Set-Handling" title="Character Set Handling"> |
| <link rel="prev" href="Restartable-multibyte-conversion.html#Restartable-multibyte-conversion" title="Restartable multibyte conversion"> |
| <link rel="next" href="Generic-Charset-Conversion.html#Generic-Charset-Conversion" title="Generic Charset Conversion"> |
| <link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> |
| <!-- |
| This file documents the GNU C library. |
| |
| This is Edition 0.12, last updated 2007-10-27, |
| of `The GNU C Library Reference Manual', for version |
| 2.8 (Sourcery G++ Lite 2011.03-41). |
| |
| Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2001, 2002, |
| 2003, 2007, 2008, 2010 Free Software Foundation, Inc. |
| |
| Permission is granted to copy, distribute and/or modify this document |
| under the terms of the GNU Free Documentation License, Version 1.3 or |
| any later version published by the Free Software Foundation; with the |
| Invariant Sections being ``Free Software Needs Free Documentation'' |
| and ``GNU Lesser General Public License'', the Front-Cover texts being |
| ``A GNU Manual'', and with the Back-Cover Texts as in (a) below. A |
| copy of the license is included in the section entitled "GNU Free |
| Documentation License". |
| |
| (a) The FSF's Back-Cover Text is: ``You have the freedom to |
| copy and modify this GNU manual. Buying copies from the FSF |
| supports it in developing GNU and promoting software freedom.''--> |
| <meta http-equiv="Content-Style-Type" content="text/css"> |
| <style type="text/css"><!-- |
| pre.display { font-family:inherit } |
| pre.format { font-family:inherit } |
| pre.smalldisplay { font-family:inherit; font-size:smaller } |
| pre.smallformat { font-family:inherit; font-size:smaller } |
| pre.smallexample { font-size:smaller } |
| pre.smalllisp { font-size:smaller } |
| span.sc { font-variant:small-caps } |
| span.roman { font-family:serif; font-weight:normal; } |
| span.sansserif { font-family:sans-serif; font-weight:normal; } |
| --></style> |
| <link rel="stylesheet" type="text/css" href="../cs.css"> |
| </head> |
| <body> |
| <div class="node"> |
| <a name="Non-reentrant-Conversion"></a> |
| <a name="Non_002dreentrant-Conversion"></a> |
| <p> |
| Next: <a rel="next" accesskey="n" href="Generic-Charset-Conversion.html#Generic-Charset-Conversion">Generic Charset Conversion</a>, |
| Previous: <a rel="previous" accesskey="p" href="Restartable-multibyte-conversion.html#Restartable-multibyte-conversion">Restartable multibyte conversion</a>, |
| Up: <a rel="up" accesskey="u" href="Character-Set-Handling.html#Character-Set-Handling">Character Set Handling</a> |
| <hr> |
| </div> |
| |
| <h3 class="section">6.4 Non-reentrant Conversion Function</h3> |
| |
| <p>The functions described in the previous chapter are defined in |
| Amendment 1<!-- /@w --> to ISO C90<!-- /@w -->, but the original ISO C90<!-- /@w --> standard |
| also contained functions for character set conversion. The reason that |
| these original functions are not described first is that they are almost |
| entirely useless. |
| |
| <p>The problem is that all the conversion functions described in the |
| original ISO C90<!-- /@w --> use a local state. Using a local state implies that |
| multiple conversions at the same time (not only when using threads) |
| cannot be done, and that you cannot first convert single characters and |
| then strings since you cannot tell the conversion functions which state |
| to use. |
| |
| <p>These original functions are therefore usable only in a very limited set |
| of situations. One must complete converting the entire string before |
| starting a new one, and each string/text must be converted with the same |
| function (there is no problem with the library itself; it is guaranteed |
| that no library function changes the state of any of these functions). |
| <strong>For the above reasons it is highly requested that the functions |
| described in the previous section be used in place of non-reentrant |
| conversion functions.</strong> |
| |
| <ul class="menu"> |
| <li><a accesskey="1" href="Non_002dreentrant-Character-Conversion.html#Non_002dreentrant-Character-Conversion">Non-reentrant Character Conversion</a>: Non-reentrant Conversion of Single |
| Characters. |
| <li><a accesskey="2" href="Non_002dreentrant-String-Conversion.html#Non_002dreentrant-String-Conversion">Non-reentrant String Conversion</a>: Non-reentrant Conversion of Strings. |
| <li><a accesskey="3" href="Shift-State.html#Shift-State">Shift State</a>: States in Non-reentrant Functions. |
| </ul> |
| |
| </body></html> |
| |
