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5.25.4 Defining library interfaces

You can give a name to a bunch of C function declarations (a library interface), as follows:

     c-library lseek-lib
     \c #define _FILE_OFFSET_BITS 64

The effect of giving such a name to the interface is that the generated files will contain that name, and when you use the interface a second time, it will use the existing files instead of generating and compiling them again, saving you time. Note that even if you change the declarations, the old (stale) files will be used, probably leading to errors. So, during development of the declarations we recommend not using c-library.

Note that the library name is not allocated in the dictionary and therefore does not shadow dictionary names. It is used in the file system, so you have to use naming conventions appropriate for file systems. Also, you must not call a function you declare after c-library before you perform end-c-library.

A major benefit of these named library interfaces is that, once they are generated, the tools used to generated them (in particular, the C compiler and libtool) are no longer needed, so the interface can be used even on machines that do not have the tools installed.

c-library-name       c-addr u –         gforth       “c-library-name”

Start a C library interface with name c-addr u.

c-library       "name" –         gforth       “c-library”

Parsing version of c-library-name

end-c-library              gforth       “end-c-library”

Finish and (if necessary) build the latest C library interface.