Chapter 9

The added section starts with a new key to include additional libraries to link to:

 LIBS              => [  ], # e.g.,   lm 

This configuration variable is actually a little more complicated than it seems. You 

might be tempted to fill it with a list of libraries to link to:

 LIBS             => [" lm", " lfoo", " lbar"],  # ERROR: only links to  lm

However, the list assigned to LIBS is actually a list of complete library sets. The first one 

that  works  on the target platform will be used. This allows you to specify sets that 

work on different operating systems without having to actually write code to do the 

testing. If you need to link to three libraries, then all three must be in a single string:

 LIBS             => [" lm  lfoo  lbar"],  # link to 3 libraries

The next new line allows you to add a  D command line option to the compi 

lation of your module's C code:

 DEFINE           =>   , # e.g.,   DHAVE_SOMETHING 

Next is a line to add  I include directories:

 INC               =>   , # e.g.,   I/usr/include/other 

and a line to include object files in the build explicitly:

# Un comment this if you add C files to link with later:

#  OBJECT          =>  $(O_FILES) , # link all the C files too

This line is commented out because using it requires you to explicitly list all the 

object files to be compiled. For example, the functional equivalent of not specify 

ing an OBJECT key is

 OBJECT          =>  MIME.o 

or, using the Makefile variables:

 OBJECT          =>  $(O_FILES) 

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