PCRE_README.html revision 1.1.1.3
1 1.1 tron <!doctype html public "-//W3C//DTD HTML 4.01 Transitional//EN" 2 1.1 tron "http://www.w3.org/TR/html4/loose.dtd"> 3 1.1 tron 4 1.1 tron <html> 5 1.1 tron 6 1.1 tron <head> 7 1.1 tron 8 1.1 tron <title>Postfix PCRE Support</title> 9 1.1 tron 10 1.1.1.3 christos <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 11 1.1 tron 12 1.1 tron </head> 13 1.1 tron 14 1.1 tron <body> 15 1.1 tron 16 1.1 tron <h1><img src="postfix-logo.jpg" width="203" height="98" ALT="">Postfix PCRE Support</h1> 17 1.1 tron 18 1.1 tron <hr> 19 1.1 tron 20 1.1 tron <h2>PCRE (Perl Compatible Regular Expressions) map support</h2> 21 1.1 tron 22 1.1 tron <p> The optional "pcre" map type allows you to specify regular 23 1.1 tron expressions with the PERL style notation such as \s for space and 24 1.1 tron \S for non-space. The main benefit, however, is that pcre lookups 25 1.1 tron are often faster than regexp lookups. This is because the pcre 26 1.1 tron implementation is often more efficient than the POSIX regular 27 1.1 tron expression implementation that you find on many systems. </p> 28 1.1 tron 29 1.1 tron <p> A description of how to use pcre tables, including examples, 30 1.1 tron is given in the <a href="pcre_table.5.html">pcre_table(5)</a> manual page. Information about PCRE 31 1.1 tron itself can be found at <a href="http://www.pcre.org/">http://www.pcre.org/</a>. </p> 32 1.1 tron 33 1.1.1.3 christos <h2>Using Postfix packages with PCRE support</h2> 34 1.1 tron 35 1.1.1.3 christos <p> To use pcre with Debian GNU/Linux's Postfix, or with Fedora or 36 1.1.1.3 christos RHEL Postfix, all you 37 1.1 tron need is to install the postfix-pcre package and you're done. There 38 1.1 tron is no need to recompile Postfix. </p> 39 1.1 tron 40 1.1.1.3 christos <h2>Building Postfix from source with PCRE support</h2> 41 1.1 tron 42 1.1.1.3 christos <p> These instructions assume that you build Postfix from source 43 1.1.1.3 christos code as described in the <a href="INSTALL.html">INSTALL</a> document. </p> 44 1.1 tron 45 1.1.1.3 christos <p> To build Postfix from source with pcre support, you need a pcre 46 1.1.1.3 christos library. Install a vendor package, or download the source code from 47 1.1.1.3 christos locations in <a href="https://www.pcre.org/">https://www.pcre.org/</a> and build that yourself. 48 1.1.1.3 christos 49 1.1.1.3 christos <p> Postfix can build with the pcre2 library or the legacy pcre 50 1.1.1.3 christos library. It's probably easiest to let the Postfix build procedure 51 1.1.1.3 christos pick one. The following commands will first discover if the pcre2 52 1.1.1.3 christos library is installed, and if that is not available, will discover 53 1.1.1.3 christos if the legacy pcre library is installed. </p> 54 1.1.1.3 christos 55 1.1.1.3 christos <blockquote> 56 1.1.1.3 christos <pre> 57 1.1.1.3 christos $ make -f Makefile.init makefiles 58 1.1.1.3 christos $ make 59 1.1.1.3 christos </pre> 60 1.1 tron </blockquote> 61 1.1 tron 62 1.1.1.3 christos <p> To build Postfix explicitly with a pcre2 library (Postfix 3.7 63 1.1.1.3 christos and later): </p> 64 1.1.1.3 christos 65 1.1.1.3 christos <blockquote> 66 1.1.1.3 christos <pre> 67 1.1.1.3 christos $ make -f Makefile.init makefiles \ 68 1.1.1.3 christos "CCARGS=-DHAS_PCRE=2 `pcre2-config --cflags`" \ 69 1.1.1.3 christos "<a href="PCRE_README.html">AUXLIBS_PCRE</a>=`pcre2-config --libs8`" 70 1.1.1.3 christos $ make 71 1.1.1.3 christos </pre> 72 1.1.1.3 christos </blockquote> 73 1.1 tron 74 1.1.1.3 christos <p> To build Postfix explicitly with a legacy pcre library (all 75 1.1.1.3 christos Postfix versions): </p> 76 1.1 tron 77 1.1 tron <blockquote> 78 1.1 tron <pre> 79 1.1.1.3 christos $ make -f Makefile.init makefiles \ 80 1.1.1.3 christos "CCARGS=-DHAS_PCRE=1 `pcre-config --cflags`" \ 81 1.1.1.2 christos "<a href="PCRE_README.html">AUXLIBS_PCRE</a>=`pcre-config --libs`" 82 1.1.1.3 christos $ make 83 1.1 tron </pre> 84 1.1 tron </blockquote> 85 1.1 tron 86 1.1.1.2 christos <p> Postfix versions before 3.0 use AUXLIBS instead of <a href="PCRE_README.html">AUXLIBS_PCRE</a>. 87 1.1.1.2 christos With Postfix 3.0 and later, the old AUXLIBS variable still supports 88 1.1.1.2 christos building a statically-loaded PCRE database client, but only the new 89 1.1.1.2 christos <a href="PCRE_README.html">AUXLIBS_PCRE</a> variable supports building a dynamically-loaded or 90 1.1.1.2 christos statically-loaded PCRE database client. </p> 91 1.1 tron 92 1.1 tron <blockquote> 93 1.1.1.2 christos 94 1.1.1.2 christos <p> Failure to use the <a href="PCRE_README.html">AUXLIBS_PCRE</a> variable will defeat the purpose 95 1.1.1.2 christos of dynamic database client loading. Every Postfix executable file 96 1.1.1.2 christos will have PCRE library dependencies. And that was exactly 97 1.1.1.2 christos what dynamic database client loading was meant to avoid. </p> 98 1.1.1.2 christos 99 1.1 tron </blockquote> 100 1.1 tron 101 1.1 tron <h2>Things to know</h2> 102 1.1 tron 103 1.1 tron <ul> 104 1.1 tron 105 1.1 tron <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, 106 1.1 tron each pattern is applied to the entire input string. Depending on 107 1.1 tron the application, that string is an entire client hostname, an entire 108 1.1 tron client IP address, or an entire mail address. Thus, no parent domain 109 1.1 tron or parent network search is done, "user@domain" mail addresses are 110 1.1 tron not broken up into their user and domain constituent parts, and 111 1.1 tron "user+foo" is not broken up into user and foo. </p> 112 1.1 tron 113 1.1 tron <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 114 1.1 tron not allowed to do $number substitution in lookup results that can 115 1.1 tron be security sensitive: currently, that restriction applies to the 116 1.1 tron local <a href="aliases.5.html">aliases(5)</a> database or the <a href="virtual.8.html">virtual(8)</a> delivery agent tables. 117 1.1 tron </p> 118 1.1 tron 119 1.1 tron </ul> 120 1.1 tron 121 1.1 tron </body> 122 1.1 tron 123 1.1 tron </html> 124
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