+which will build a Universal binary containing targets for PPC, i386 and x86_64 processor architectures that'll run on all Macintosh OS X versions from 10.5 (Leopard) and upwards. The disadvantage of bundling multiple processor architectures is that the build is consequently limited to using the bundled PCRE implementation, which is a Bad Idea™ (see section 1.1 for details).
+
+The most common usage therefore would be as follows:
+
+./build.sh snowleopardx64 -pcre
+
+which will build a binary targetting only x86_64 processors (note that OS X has supported only x86_64 since Snow Leopard).
+
+Running build.sh without supplying any parameters will cause it to list all the possible options, should you have an alternative target requirement.
+
+
+1.1 Consider whether to use external or bundled PCRE.
+
+Privoxy uses the Perl Compatible Regular Expressions (PCRE) library when matching its rules against the folder-and-file part of a target URL. Privoxy's source ships with a version of the PCRE library that, whilst convenient, is very out of date (version 3). The recommendation is therefore to download, make and install the latest PCRE distribution to your build machine and compile Privoxy against that instead.
+
+To support this, build.sh takes an optional second parameter (-pcre) which tells it to look for an installation of the PCRE library in the standard location on the build machine (/usr/local/lib). The obvious corrollary is that you must have downloaded, configured, made and installed PCRE before building Privoxy if you wish to link to the external library.
+
+There are three important further considerations that this approach brings. Firstly, you must ensure when building PCRE that you build it to support the same minimum version of OS X that you wish Privoxy to support (note that by default PCRE's build process assumes the OS X version of the build machine is the minimum version to be supported). Failure to match the minimum supported versions will mean that, whilst Privoxy will still build, the external PCRE check will fail and you will end up compiling in the bundled PCRE, not linking to the external PCRE library as you'd intended.
+
+The second consideration when using external PCRE is that the PCRE build process allows only single-architecture libraries to be built, which means that the Privoxy binary you build must also be single-architecture. The outcome of not following this rule would be as above; you will succeed in building Privoxy but it will compile in the bundled PCRE rather than linking to the external library.
+
+The final consideration is that if you are building Privoxy for multiple different targets, you must also build PCRE independently for each of those targets and, when building that target's Privoxy release, ensure that the correct version of PCRE is present in /usr/local/lib.
+
+A sample command line that will build Privoxy with external PCRE to run on Snow Leopard and higher on 64 bit Intel Macs is:
+
+./build.sh snowleopardx64 -pcre
+
+This example assumes that a valid build of PCRE supporting x86_64 processors and a minimum OS X version of 10.6 is present in /usr/local/lib.
+
+
+1.2 Builds for the Sourceforge Privoxy project release set
+
+Three packages are built for this target release set:
+
+./build.sh snowleopardx64 -pcre
+./build.sh tigeri386 -pcre
+./build.sh tigerppc -pcre
+
+The rationale is that the first one will support 64 bit systems running 10.6 and higher, the second 32 bit Intel running 10.4 or 10.5, and the last one PPC systems running 10.4 or 10.5.
+
+Note that in order to build each version, the pcre library fileset must be changed to match the architecture being built.