EWL uses the definitions of preprocessor macros to specify the capabilities of the platform on which EWL runs and to choose the policies that EWL uses to manage its resources. EWL provides a prefix file for each build target that EWL runs on. An EWL prefix file is a C header file that contains a list of macro definitions. To compile a customized version of EWL for your build target, copy your build target's prefix file then customize its macro definitions.
For example, to compile a custom version of EWL C for the SockSort build target, find and copy the header file named ansi_prefix.SockSort.h. Edit the contents of your copy of this prefix file, then add this customized file to your project to build a new, custom EWL C library. Add this customized library and your prefix file to your projects to use your custom standard library.