4

Libraries

You can use a module unit as a library of useful functions. The simplest way to do so is to create a source file containing the definitions of your library routines and then compile it using the -coption. You can then link the resulting .o file to any number of files. For convenience, you probably should create a header file containing the routine declarations for the library.

A simple library as described above has two problems:

•When a library grows in size, it may become inconvenient to store its source in a single file, both for ease of editing and so you can avoid recompiling a large file when you change only part of it.

On the other hand, it would be inconvenient to have to name many library modules on the command-line when you link your program. Thus, it would be helpful to be able to combine a number of library modules.

•Several programs that you run at the same time may share the same library. Under the scheme described above, each program has its own copy of the library. It saves space and even I/O time if several programs share library code.

Both problems have solutions. First, you can combine or archive modules together. Secondly, you can create a shared library.

See the Solaris documentation on the linker and libraries for information on creating archived and shared libraries.

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Pascal 4.0 User’s Guide