buffer_sizes.html 2.4 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960
  1. <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
  2. <HTML>
  3. <HEAD>
  4. <TITLE>Buffer Sizes</TITLE>
  5. <LINK REL="stylesheet" HREF="../../../../boost.css">
  6. <LINK REL="stylesheet" HREF="../theme/iostreams.css">
  7. </HEAD>
  8. <STYLE>
  9. DT A { /*text-decoration:none*/ }
  10. LI A { /*text-decoration:none;*/ font: 80% Verdana, Tahoma, Arial, Helvetica, sans-serif }
  11. </STYLE>
  12. <BODY>
  13. <!-- Begin Banner -->
  14. <H1 CLASS="title">Buffer Sizes</H1>
  15. <HR CLASS="banner">
  16. <!-- End Banner -->
  17. <DL class="page-index">
  18. <DT><A href="#overview">Overview</A></DT>
  19. <DT><A href="#headers">Headers</A></DT>
  20. <DT><A href="#synopsis">Synopsis</A></DT>
  21. </DL>
  22. <HR>
  23. <A NAME="overview"></A>
  24. <H2>Overview</H2>
  25. <P>
  26. The macros <CODE>BOOST_IOSTREAMS_DEFAULT_DEVICE_BUFFER_SIZE</CODE>, <CODE>BOOST_IOSTREAMS_DEFAULT_FILTER_BUFFER_SIZE</CODE> and <CODE>BOOST_IOSTREAMS_DEFAULT_PBACK_BUFFER_SIZE</CODE> can be used to configure the default sizes of buffers allocated by the Iostreams library when a <A HREF="../concepts/filter.html">Filter</A> or <A HREF="../concepts/device.html">Device</A> is attached to a <A HREF="../guide/generic_streams.html#stream_buffer"><CODE>stream_buffer</CODE></A> or <A HREF="../guide/generic_streams.html#stream"><CODE>stream</CODE></A>, or when it is added to a <A HREF="../classes/chain.html">chain</A>.
  27. </P>
  28. <P>The default values are subject to change in future versions of the Iostreams library.</P>
  29. <A NAME="headers"></A>
  30. <H2>Headers</H2>
  31. <DL class="page-index">
  32. <DT><A CLASS="header" HREF="../../../../boost/iostreams/constants.hpp"><CODE>&lt;boost/iostreams/constants.hpp&gt;</CODE></A></DT>
  33. </DL>
  34. <A NAME="synopsis"></A>
  35. <H2>Synopsis</H2>
  36. <PRE CLASS='broken_ie'><SPAN CLASS='preprocessor'>#define</SPAN> BOOST_IOSTREAMS_DEFAULT_DEVICE_BUFFER_SIZE 4096
  37. <SPAN CLASS='preprocessor'>#define</SPAN> BOOST_IOSTREAMS_DEFAULT_FILTER_BUFFER_SIZE 128
  38. <SPAN CLASS='preprocessor'>#define</SPAN> BOOST_IOSTREAMS_DEFAULT_PBACK_BUFFER_SIZE 4</PRE>
  39. <!-- Begin Footer -->
  40. <P CLASS="copyright">&copy; Copyright 2008 <a href="http://www.coderage.com/" target="_top">CodeRage, LLC</a><br/>&copy; Copyright 2004-2007 <a href="https://www.boost.org/users/people/jonathan_turkanis.html" target="_top">Jonathan Turkanis</a><br/>Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at <A HREF="http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</A>)
  41. </P>
  42. <!-- End Footer -->
  43. </BODY>