# SWIG Tcl Examples

The following examples illustrate the use of SWIG with Tcl.

- simple. A minimal example showing how SWIG can be used to wrap a C function and a global variable.
- constants. This shows how preprocessor macros and certain C declarations are turned into constants.
- variables. How SWIG can be used to wrap C global variables.
- value. How to pass and return structures by value.
- class. How wrap a simple C++ class.
- reference. C++ references.
- pointer. Simple pointer handling.
- funcptr. Pointers to functions.

## Compilation Issues

- To create a Tcl extension, SWIG is run with the following options:

  >     % swig -tcl interface.i

- Please see the Windows page in the main manual for information on using the examples on Windows.

- The compilation of examples is done using the file `Example/Makefile`. This makefile performs a manual module compilation which is platform specific. Typically, the steps look like this (Linux):

  >     unix % swig -tcl interface.i
  >     unix % gcc -fPIC -c interface_wrap.c -I/usr/local/include
  >     unix % gcc -shared interface_wrap.o $(OBJS) -o interface.so
  >     unix % tclsh8.3
  >     % load ./interface.so
  >     % blah ...

## Compatibility

The examples have been extensively tested on the following platforms:

- Linux
- Solaris

Your mileage may vary. If you experience a problem, please let us know by contacting us on the mailing lists.