Using the Graphics Module
Author: Christian.Queinnec@lip6.fr

## Using the `Graphics` Module

Utilization of the library `Graphics` differs depending on the system and the compilation mode used. We will not cover applications other than usable under the interactive toplevel of Objective CAML. Under the Windows and MacOS systems the interactive working environment already preloads this library. To make it available under Unix, it is necessary to create a new toplevel. This depends on the location of the X11 library. If this library is placed in one of the usual search paths for C language libraries, the command line is the following:

    ocamlmktop -custom -o mytoplevel graphics.cma -cclib -lX11

It generates a new executable`mytoplevel` into which the library `Graphics` is integrated. Starting the executable works as follows:

    ./mytoplevel

If, however, as under Linux, the library X11 is placed in another directory, this has to be indicated to the command `ocamlmktop`:

    ocamlmktop -custom -o mytoplevel graphics.cma -cclib \
               -L/usr/X11/lib -cclib -lX11

In this example, the file `libX11.a` is searched in the directory `/usr/X11/lib`.
A complete description of the command `ocamlmktop` can be found in chapter 7.