Using the C Math Library

Defining a Print Handler  

In the past, when there were only character-based terminals, input and output were very simple; programs used scanf for input and printf for output. Graphical user interfaces (GUIs) make input and output routines more complex. The MATLAB C Math Library is designed to run on both character-based terminals and in graphical, windowed environments. Simply using printf or a similar routine is fine for character-terminal output, but insufficient for output in a graphical environment.

The MATLAB C Math Library performs some output; in particular it displays error messages and warnings, but performs no input. To support programming in a graphical environment, the library allows you to determine how the library displays output.

The MATLAB C Math Library's output requirements are very simple. The library formats its output into a character string internally, and then calls a function that prints the single string. If you want to change where or how the library's output appears, you must provide an alternate print handler.

Replacing the Default Library Error Handler

Providing Your Own Print Handler