Target specific issues: Linux.

There are several issues on Linux that need to be taken care of:

The Linux version of the Graph unit uses the libvga library. This library works on the console, not under X.

If you get an error similar to

/usr/ind: cannot find -lvga

This can mean one of two things: either libvga and it's development package is not installed properly, or the directory where it is installed is not in the linker path.

To remedy the former, you should install both the libvga package and libvga-devel package (or compile and install from scratch).

To remedy the latter, you should add the path to the compiler command-line using the -Fl option.

Programs using libvga need root privileges to run. You can make them setuid root with the following command:

chown root.root myprogram
chmod u+s myprogram

The libvga library will give up the root privileges after it is initialized.

there is an experimental version of the Graphics library available that uses GGI to do all the drawing, but it is not well tested. It's called ggigraph and is distributed in source form only.

Do not use the CRT unit together with the Graph unit: the console may end up in an unusable state. Instead, the ncurses unit may function fine.