HP OpenVMS I/O User's Reference Manual

This manual provides technical documentation for system programmers on directly using file-structured and real-time I/O device drivers in the OpenVMS operating system. It covers the Queue I/O (QIO) interface to ancillary control processes (ACPs), disk drivers, magnetic tape drivers, the mailbox driver, the terminal driver, the pseudoterminal driver, the shadow-set virtual unit driver, the Generic SCSI class driver, and Local Area Network (LAN) device drivers. It also details optional features for improving I/O performance, such as Fast I/O and Fast Path, and provides VAX MACRO programming examples for driver interaction.