A method, apparatus and computer program product, the method comprising: opening a storage volume associated with a mainframe computer executing z/OS operating system; obtaining access to a required area of the storage volume; receiving a call from a program programmed in a high level programming language and executed on the mainframe computer, to execute a user channel program, wherein the user channel program may refer to any location within the required area of the storage volume; and processing the user channel program to obtain channel command words and provide the channel command words to Execute Channel Program (EXCP).
