Library /sys$common/syshlp/helplib.hlb  —  LD  New features V9.2
 	V9.2 has the following new features:

 	The major new feature is variable container file support for tape. This
 	allows a file on disk to be used as a tape device, without having to
 	preallocate a certain amount of blocks. This is enabled at CONNECT time
 	with the qualifier /EXTEND. Also, a limit may be placed on the maximum
 	container file size. The default is unlimited, which means that
 	extending the file will stop as soon as the underlaying disk is full.

 	Example:

 	   $ LM CREATE TAPE.DSK/SIZE=0
 	   $ LM CONNECT/LOG/FULL/EXTEND=10000/LIMIT=5000000 TAPE.DSK LMA1:
 	   %LM-I-CONNECTED, Connected $2$LMA1: to $4$DKA400:[JUR.LD.V92.SRC]TAPE.DSK;1
 	   -LM-I-OPTIONS, Tape unit, Tape loaded, Extend file on demand (size=10000, limit=5000000)
 	   %LM-I-METADATA, Metadata available

 	   Version:                 1
 	   Creator:                 JUR
 	   Process name:                  EH?
 	   Account:
 	   UIC:                     [100,100]
 	   Created on system:       THENET
 	   VMS version:             V8.3
 	   Time at creation:         1-MAR-2009 21:30:28.51
 	   Time at last connect:     1-MAR-2009 21:30:36.53
 	   Time at last disconnect:  1-MAR-2009 21:30:28.51
 	   Data start:              1
 	   Data size:               0
 	   Flags:                   tagsinuse
 	   Checksum:                30F9EAF7

 	This will create a virtual tape of initially 0 blocks in size, and the
 	extension of the container file will be done with 10000 blocks at a
 	time. There's a limit of 5000000 blocks, if the file grows to that
 	limit then the end of tape marker will be returned at 95% of the
 	maximum capacity.

 	After writing the tape and dismounting it, excess blocks can be removed
 	from the container file with LM DISCONNECT/TRUNCATE or
 	LM UNLOAD/TRUNCATE. This will effectively truncate the container file
 	to the maximum logical block where data has been written.

 	Specifying /LIMIT without /EXTEND on the CONNECT command is not allowed.
 	The default extension limit for /EXTEND is 65536 blocks if not
 	specified. Specifying /LIMIT=0 is the same as not specifying /LIMIT.

 	Bug fixes:

 	IO$_SETMODE to a tape device will now set the correct default device
 	buffer size.

 	Under very specific circumstances a skip reverse operation to tape
 	resulted in a read request from disk with a random number of bytes.
 	Some controllers rejected the command with SS$_CTRLERR, other errors
 	could be an SS$_BUGCHECK from the driver itself.

 	A system crash could occur when running LD$STARTUP.COM or LM$STARTUP
 	on a system which was very low on nonpaged pool. Doing that right now
 	will return an error.

 	The known issues for V9.0 are the same as for V9.2.
Close Help