The source file that you download is in a compressed, tar archive and must be uncompressed using the gzip command. In the same directory as the downloaded bundle, type the following:
gzip -d postfix-2.0.10.tar.gz
This uncompresses the file and produces a tar file without the .gz extension. Next, untar the file:
tar -xf postfix-2.0.10.tar
This creates a directory called postfix-2.0.10 below the current directory. Set that directory as your current directory for the rest of the compilation:
If you accept all of the default parameters for building Postfix, compiling is as simple as executing make in the top-level directory of the distribution:
Executing make creates a Makefile for your particular platform, which is in turn used to compile Postfix for your system. If you don't need any changes to the default build, you can skip ahead to the Section C.4 section.
The file makedefs contains platform-specific information that Postfix uses when configuring the package for your system. If you are curious, you can look at the file to see which parameters Postfix uses for your platform. It identifies your environment and creates the macros and definitions that are used in the Makefile for building Postfix on your system. The resultant Makefile is invoked by the make command which in turn calls your compiler and linker to build the Postfix system. When you type make as above, all of this happens automatically, so you don't normally ...