OpenVMS I/O User's Reference Manual

This manual provides comprehensive documentation for system programmers on performing direct I/O operations in the OpenVMS operating environment. It covers:

• ACP-QIO Interface: Detailed explanation of the Queue I/O (QIO) interface for interacting with file system ancillary control processes (ACPs).
• Device Drivers: In-depth coverage of drivers for disk storage (including DSA and SCSI), magnetic tape subsystems, mailboxes for interprocess communication, terminal drivers (including LAT), and pseudoterminal drivers.
• Network Drivers: Detailed information on local area network (LAN) device drivers and their configurations.
• Performance Features: Guidelines for using Fast I/O and Fast Path for optimizing I/O performance on Alpha and I64 systems.
• Reference Material: Extensive tables of I/O function codes, modifiers, and status returns for each driver type.