Customizing Your Build

Customizing Your Build

The file makedefs contains platform-specific information that Postfix uses when con- figuring 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 need to worry about this file.

If you want to change any of the parameters for your environment, you can execute the build in two steps. The command make makefiles creates a new Makefile based on parameters that you specify on the command line. To set specific parameters, simply define variables on the command line. For example, you can use a different compiler from the default that Postfix chooses for your environment. The following example works on an HP-UX system to be sure that make finds the correct compiler:

$ make makefiles CC="/opt/ansic/bin/cc -Ae"

You would, of course, specify the path to your own compiler plus any necessary options. If you need to specify an additional directory for header files on your sys- tem, define CCARGS to include your directory:

$ make makefiles CCARGS="-I /usr/local/include/"

And, of course, you can combine options:

$ make makefiles CC="/opt/ansic/bin/cc -Ae" CCARGS="-I /usr/local/include"