#include <IO.h> GapIO *open_db( char *project, char *version, int *status, int create, int read_only);
open_db opens existing databases or creates new databases.
The database to be opened or created has unix filenames of
"project.version" and "project.version.aux".
The create variable should be 0 or 1. A value of 1 indicates that this
database is to be created. This will not be done if there is a file named
"project.version.BUSY", in which case the status variable is
set to contain
The read_only variable should be 0 or 1. A value of 1 indicates that the
database should be opened in read only mode, otherwise read/write access is
desired. If the database is busy then the database may still be opened in read
only mode instead. In this case the status variable is set to contain
The GapIO structure is then initialised and returned. A successful return will leave status containing 0. For failure, the function returns NULL.