DUCM/DYC Release 5 11th April 1990 This is a distribution of large disk handlers for DU (MSCP) disks. Full source and documentation is included. These have been tested and work fine on Fujitsu Eagles running TSX-Plus Version 6.4. A TSX-mappable RX03 floppy disk handler (DYC Version 3) is included. It can cope with Sigma, Dilog, MTI, DSD and DEC controllers, and uses the 22-bit addressing ability of the first three of these. If run as a programme it allows you to format discs, requiring no privileges under TSX-plus. Concerning the files on this disc: the abstract is ABSTRA.CT, and this file is READ.ME. There are three sections to this distribution: (1) the DUCM section, which is the handler for DU (MSCP) discs; (2) the WA section, which is the special handler for using large discs under TSX-plus; and (3) the DYC handler, which is an RX03 handler for Sigma/Dilog controllers, and which may be mapped under TSX-plus. Please read DUCM.DOC to find out what to do. [It consists of three manuals, a basic one, and the full ones for DUCM and WA. You do not have to read the full ones to be able to use these handlers.] DUCM.DIS and DYC.DIS give a sort of overview of the contents of each of the logical discs (on DUCM.DSK and DYC.DSK respectively). They are the command files used to create this distribution. Version 2b fixed an occasional data corruption problem which occurred rarely on heavily loaded and heavily swapping systems. Version 2c included fixes to the serious error code, and has had time-out support added. Version 2d tidies yet another bug, and places a safety restricion on the timeout code under TSX-plus. Version 3 added the MSCP BYPASS facility (use with care!). This facility requires that the user MSCP buffer size be 60 (octal) - the same as in the handler. As the DEC subroutines JREAD/JWRITE and IGTDUS use this size, it should not be a significant problem. [Despite having used the buffer address code from DEC's DU handler for the XM monitor version of this handler, I am very suspicious that an XM system running multiple jobs all of which are rapidly accessing the disc, could be crashed by both this handler and DEC's. This is due to the primitive form of DEC's $RELOC.] Version 3a fixed a bug if there were a time-out error during initialization. Version 3b added an extra FORK level to timeout initialization, as TSX V6.31 fell over in funny ways if this were merely included in normal init code. Version 4 rewrote large chunks of the handler to get around a nasty bug in TSX V6.31 (NOT gotten around in V3b of DUCM). Version 4a tidied the Unit Size SPFUN, and allowed changing of any unit & partition under TSX-plus provided that the request comes from job 1. Version 4b corrected a crash-code bug, and added extra code for pseudo- interrupt generation as a mapped handler under TSX-plus. Version 4c allowed changing everyone's units 6 & 7 from job 1 under TSX, corrected a bug in the /D/V area, and took the time-out value back to 10 seconds. Version 4d allowed alteration of the boot device name, for multi-controller systems. Version 4e (sorry so many in so short a time!) fixed a bug in /D code where the boot unit/partition table was not updated. Version 5 added direct comparison SPFUNs, and tidied up various bits of code. It revealed problems with the Emulex SC03 controller, and (hopefully!) we have managed to get around most of these. Code was added to support the RT SJ monitor better. Chester Wilson Charleville 4470 Australia.