ParsePathFile(char filename) is used to open the file which contains the path. It then builds a link list of nodes and they attributes. It calls read_file, parse_path_string, and build_path.
PrintPath() is used for debugging. It prints the path list of nodes and they attribute.
GetPathAttribute(char *attr_label) it returns char string of the path Attribute or NULL if the path doesn't have that attribute defined.
GetNodeAttribute(int node_id, char *attr_label) it returns the char string for the node attribute for the node_id. If the node doesn't have the node attribute it will return the global path attribute. If the path doesn't have such a attribute it returns NULL.
GetPathLength() returns the number of node in a given path.