DGT DGT is one of the more powerful "foreign tape" utilities that are around. It was written initially for tape positioning, but has been growing for some time and now can handle numerous tape data formats. Among its major supported formats are: ASCII or EBCDIC input in fixed length records of any length blocked up to 100 (with some minor restrictions on total record length). ASCII or EBCDIC output in 80 byte records blocked up to 100 [note: it'd be fairly easy to make record length variable but I never needed to] per tape block Data General RDOS tape input UNIX TAR tape input (creates a separate file with the UNIX pathnames and makes RSX-compatible names out of the last part of the pathnames. Also flags binary files. BCD tapes from old IBM equipment (easy to change char set) DGT can also position tape in either direction by any number of files or records, write endfiles, rewind tape, and set tape characteristics (e.g. parity or density) to anything the driver allows. It has a HELP command (just say DGT HELP if installed) to give key letters and meanings. DGT commands are of the format ,, where information past the blockfactor is often not needed and is optional if not required. is an ASCII command name which I usually abbreviate to a single letter. Only the first letter is examined of the string in any case. A space or comma after the string is required. The unit number is then given as a decimal number for the tape. DGT is customized for MT:, MM:, MS:, or whatever by editing the ALUN.MAC file. ALUN gets the number in and assigns MAGLUN (defined in the TKB file with a GBLDEF) to the appropriate device and unit. DGT works on unmounted or foreign-mounted tape, in M, M+, or IAS (or VAX VMS compatibility mode). The block factor is the number of fixed length records that fit onto one physical record on the tape. DGT is not too smart about this; if it is set up for 80 character record length (with the B command [e.g., B 0,80]) or by default and you tell it that the blocking factor is 100 [e.g. INPUT 0,100] it will write 100 records on the PDP11 even if it reads only 80 bytes on tape. To build DGT, assemble or compile the files that you find referred to in the TKB file, link, and use. When DGT needs a filename (as when reading a file from tape to PDP11, or when writing tape from a file), it prompts for it on a separate line and uses GETCML to allow this to happen from a command file. Be aware that while all commands use GETCML, the format is not normal MCR. When DGT reads 80 byte records, it will remove trailing whitespace on the read. For other record lengths, it leaves the whitespace in. On output to 80 byte records, DGT will re-insert spaces to the end of record. It has a mode to write DG RDOS tapes which is imperfect. Use the DGWRIT program instead for that purpose. It has been tested and works correctly. DGT can however read RDOS tapes fine. No special software need be written on the DG side. A minor customization is occasionally needed in DGT to go through and clear all 200 bits in characters on readin, where ASCII comes in from foreign tapes with the 200 bit set. Such data reads in and generally lists but is almost impossible to edit because of this difference in the ASCII codes used. PDP11 and VAX always clear the 200 bit. You may want to use MTQIO or ASCEBC as utilities; they provide easy and complete tape control or ASCII <==> EBCDIC translation respectively. Glenn Everhart