7.5.2.1 AutoOpt-ed Library for AutoOpt-ed Program

The library source code must provide an option definition file that consists of only the attribute library and flag entries. The library attribute does not need any associated value, so it will generally appeary by itself on a line folowed by a semi-colon. The first flag entry must contain the following attributes:

‘name’

This name is used in the construction of a global pointer of type tOptDesc const*. It is always required.

‘documentation’

It tells AutoOpts that this option serves no normal purpose. It will be used to add usage clarity and to locate option descriptors in the library code.

‘descrip’

This is a string that is inserted in the extended usage display before the options specific to the current library. It is always required.

‘lib-name’

This should match the name of the library. This string is also used in the construction of the option descriptor pointer name. In the end, it looks like this:

extern tOptDesc const* <<lib-name>>_<<name>>_optDesc_p;

and is used in the macros generated for the library’s ‘.h’ file.

In order to compile this AutoOpts using library, you must create a special header that is not used by the client program. This is accomplished by creating an option definition file that contains essentially exactly the following:

AutoGen definitions options;
prog-name  = does-not-matter;  // but is always required
prog-title = 'also does not matter';  // also required
config-header = 'config.h'; // optional, but common
library;
#include library-options-only.def

and nothing else. AutoGen will produce only the ‘.h’ file. You may now compile your library, referencing just this ‘.h’ file. The macros it creates will utilize a global variable that will be defined by the AutoOpts-using client program. That program will need to have the following #include in its option definition file:

#include library-options-only.def

All the right things will magically happen so that the global variables named <<lib-name>>_<<name>>_optDesc_p are initialized correctly. For an example, please see the AutoOpts test script: ‘autoopts/test/library.test’.

This document was generated by Bruce Korb on August 21, 2015 using texi2html 1.82.