maria-vis is a lefty script invoked by maria in
order to visually present information to the user. The script reads
commands and directives from standard input and may write maria
query language commands to standard output. An end-of-file condition
on standard input terminates the script.
The script is built on top of the dotty script that is part of
the GraphViz package. The commands prefixed with visual in
maria issue two kinds of commands to this script: new();
or add(); followed by a newline character and a graph definition
in the dot input language. The new function in the script
displays the graph in a new window, while the add function
copies information from the graph to the last modified graph.