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diff --git a/html/PCRE_README.html b/html/PCRE_README.html new file mode 100644 index 0000000..817bbb8 --- /dev/null +++ b/html/PCRE_README.html @@ -0,0 +1,106 @@ +<!doctype html public "-//W3C//DTD HTML 4.01 Transitional//EN" + "http://www.w3.org/TR/html4/loose.dtd"> + +<html> + +<head> + +<title>Postfix PCRE Support</title> + +<meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> + +</head> + +<body> + +<h1><img src="postfix-logo.jpg" width="203" height="98" ALT="">Postfix PCRE Support</h1> + +<hr> + +<h2>PCRE (Perl Compatible Regular Expressions) map support</h2> + +<p> The optional "pcre" map type allows you to specify regular +expressions with the PERL style notation such as \s for space and +\S for non-space. The main benefit, however, is that pcre lookups +are often faster than regexp lookups. This is because the pcre +implementation is often more efficient than the POSIX regular +expression implementation that you find on many systems. </p> + +<p> A description of how to use pcre tables, including examples, +is given in the <a href="pcre_table.5.html">pcre_table(5)</a> manual page. Information about PCRE +itself can be found at <a href="http://www.pcre.org/">http://www.pcre.org/</a>. </p> + +<h2>Building Postfix with PCRE support</h2> + +<p> These instructions assume that you build Postfix from source +code as described in the <a href="INSTALL.html">INSTALL</a> document. Some modification may +be required if you build Postfix from a vendor-specific source +package. </p> + +<p> Note: to use pcre with Debian GNU/Linux's Postfix, all you +need is to install the postfix-pcre package and you're done. There +is no need to recompile Postfix. </p> + +<p> In some future, Postfix will have a plug-in interface for adding +map types. Until then, you need to compile PCRE support into Postfix. +</p> + +<p> First of all, you need the PCRE library (Perl Compatible Regular +Expressions), which can be obtained from: </p> + +<blockquote> +<a href="ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/">ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/</a>. +</blockquote> + +<p> NOTE: pcre versions prior to 2.06 cannot be used. </p> + +<p> In order to build Postfix with PCRE support you need to add +-DHAS_PCRE and a -I option for the PCRE include file to CCARGS, and +add the path to the PCRE library to <a href="PCRE_README.html">AUXLIBS_PCRE</a>, for example: </p> + +<blockquote> +<pre> +make -f Makefile.init makefiles \ + "CCARGS=-DHAS_PCRE `pcre-config --cflags`" \ + "<a href="PCRE_README.html">AUXLIBS_PCRE</a>=`pcre-config --libs`" +</pre> +</blockquote> + +<p> Postfix versions before 3.0 use AUXLIBS instead of <a href="PCRE_README.html">AUXLIBS_PCRE</a>. +With Postfix 3.0 and later, the old AUXLIBS variable still supports +building a statically-loaded PCRE database client, but only the new +<a href="PCRE_README.html">AUXLIBS_PCRE</a> variable supports building a dynamically-loaded or +statically-loaded PCRE database client. </p> + +<blockquote> + +<p> Failure to use the <a href="PCRE_README.html">AUXLIBS_PCRE</a> variable will defeat the purpose +of dynamic database client loading. Every Postfix executable file +will have PCRE library dependencies. And that was exactly +what dynamic database client loading was meant to avoid. </p> + +</blockquote> + +<h2>Things to know</h2> + +<ul> + +<li> <p> When Postfix searches a <a href="pcre_table.5.html">pcre</a>: or <a href="regexp_table.5.html">regexp</a>: lookup table, +each pattern is applied to the entire input string. Depending on +the application, that string is an entire client hostname, an entire +client IP address, or an entire mail address. Thus, no parent domain +or parent network search is done, "user@domain" mail addresses are +not broken up into their user and domain constituent parts, and +"user+foo" is not broken up into user and foo. </p> + +<li> <p> Regular expression tables such as <a href="pcre_table.5.html">pcre</a>: or <a href="regexp_table.5.html">regexp</a>: are +not allowed to do $number substitution in lookup results that can +be security sensitive: currently, that restriction applies to the +local <a href="aliases.5.html">aliases(5)</a> database or the <a href="virtual.8.html">virtual(8)</a> delivery agent tables. +</p> + +</ul> + +</body> + +</html> |