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HELP DEVICE A.Sloman August 1988 The basic Input/Output (I/O) procedures in POP-11 (which are modelled on UNIX system calls) all work on objects called DEVICE RECORDS. A device record is a data structure describing a disk file (or some actual device such as a terminal or graphics device). The procedures *SYSOPEN *SYSCREATE *SYSPIPE (Unix) and *SYSMAILBOX (VMS) create such device records. *SYSREAD *SYSWRITE and * SYSFLUSH are used to read and write characters and other data via devices. *SYSCLOSE closes a file or other device. *DEVICE_OPEN_NAME, when applied to a device record returns the file name used when the device record was created. (Previously this was DEVNAME) *ISDEVICE can be used to recognise device records. *SYS_FILE_STAT can be used to find information about a file, such as its size, modification date, owner, and protection. *SYSFILESIZE is a library file defined in terms of it. For more detailed information on Input/Output procedures see REF *SYSIO, REF * SYSUTIL, and REF * CHARIO HELP *PIPEUTILS describe procedures for communicating with sub-processes via pipes (on Unix only). --- C.all/help/device -------------------------------------------------- --- Copyright University of Sussex 1988. All rights reserved. ----------