The philosophy that global variables are generally a bad idea has been adopted. In many cases, using global variables within functions hides the behaviour of a function, and therefore, it is preferable to specify all relevant information to a function in the argument list, rather than relying on any global variables. Secondly, modification of a global variable by a given function precludes the use of this function in a multi-threaded environment (two processes may attempt to modify the global variable at the same time). As a result of adopting the anti-global variable philosophy, the user of the BIC Volume IO Library often must specify many arguments to a function. This seems a small price to pay, in return for the ability to see all factors controlling the behaviour of each function in the argument list.