<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: 'Helvetica Neue'; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; ">On 28 Mar 2013, at 5:24 AM, <<a href="mailto:simh-request@trailing-edge.com">simh-request@trailing-edge.com</a>> <<a href="mailto:simh-request@trailing-edge.com">simh-request@trailing-edge.com</a>> wrote:</span></div><div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; font-family: 'Helvetica Neue'; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><span class="Apple-style-span" style="font-family: monospace; ">Google 'AA-JS16A-TC' for some Files-11 format information; I'd<span class="Apple-converted-space"> </span><br>have to think a bit on the DOS-11 format.</span></span></blockquote></div><div><br></div>RSX/VMS Files-11 tapes are ANSI labeled tapes. I know OpenVMS also used HDR3/4 labels for RMS information. There was a MOUNT option to suppress writing those labels.<div><br></div><div>I wrote an RSX/VMS program that will scan an unknown tape and decode it for you. (If anyone wants it, let me know where I should upload it.) The DOS format decoder looks for a 14 byte (physical) record at the start of the file. It is decoded by the following code:</div><div><br></div><div><div>C</div><div>C... DEC DOS labels</div><div>C</div><div> Call R50ASC ( 6, buffer( 1), ascbuf( 1) )</div><div> Call R50ASC ( 3, buffer(13), ascbuf( 7) )</div><div> ascbuf(10) = '.'</div><div> Call R50ASC ( 3, buffer( 5), ascbuf(11) )</div><div> ltemp(1) = buffer(7)</div><div> ltemp(2) = 0</div><div> mem = itemp</div><div> ltemp(1) = buffer(8)</div><div> grp = itemp</div><div> ltemp(1) = buffer(11)</div><div> ltemp(2) = buffer(12)</div><div> jday = MOD(itemp,1000)</div><div> year = itemp/1000 + 70</div><div> Call JDCONV ( jday, mon, day, year )</div><div> ltemp(1) = buffer( 9)</div><div> ltemp(2) = buffer(10)</div><div> Write (STDOUT,619) ifile, grp, mem, ascbuf, day, month(mon),</div><div> 1 year, itemp</div><div> 619 Format (//' File ', I4, ':', T34, '"', '[', O3.3, ',', O3.3, ']',</div><div> 1 13A1, 2X, I2, '-', A, '-', I2.2, ' <', O3.3, '>', '"')</div></div><div><br></div><div>The DOS label contents are:</div><div><br></div><div>Words 1-2 RAD50 characters 1-6 of the file name part (before the implied period)</div><div>Word 3 RAD50 characters 1-3 of the file type (after the implied period)</div><div>Word 4 Octal File owner's User Identification Code (group code in high-order byte, member code in low-order byte)</div><div>Word 5 Binary File creation date ( 1000 * ( year - 1970 ) + Julian day )</div><div>Word 6 Octal File protection (low-order to high-order RWED bits: read, write, extend, delete; grouped low-order to high-order for system, owner, group, world)</div><div>Word 7 RAD50 characters 7-9 of the file name part (before the implied period)</div><div><br></div><div>The references I used to write the program (back in the 1980's) are below. Which reference had the DOS label format I don't remember (if any of them did).</div><div><br></div><div><div>6 References</div><div><br></div><div>[1] American National Standards Institute, 1978, Magnetic Tape Labels</div><div> and File Structure for Information Interchange (ANSI X3.27-1978).</div><div><br></div><div>[2] Digital Equipment Corp., 1985, RSX-11M/M-Plus MCR Operations</div><div> Manual (Order no. AA-FD10A-TC).</div><div><br></div><div>[3] Digital Equipment Corp., 1985, RSX-11M-Plus Command Language</div><div> Manual (Order no. AA-FD04A-TC).</div><div><br></div><div>[4] Digital Equipment Corp., 1985, RSX-11M/M-Plus and Micro/RSX I/O</div><div> Operations Reference Manual (Order no. AA-FD14A-TC).</div><div><br></div><div>[5] Digital Equipment Corp., 1985, RSX-11M/M-Plus I/O Drivers</div><div> Reference Manual (Order no. AA-FD09A-TC).</div><div><br></div><div>[6] Digital Equipment Corp., 1984, VAX/VMS Command Definition Utility</div><div> Reference Manual (Order no. AA-Z408A-TE).</div><div><br></div><div>[7] Digital Equipment Corp., 1986, VAX/VMS DCL Dictionary (Order no.</div><div> AA-Z200C-TE).</div><div><br></div><div>[8] Digital Equipment Corp., 1984, VAX/VMS Mount Utility Reference</div><div> Manual (Order no. AA-Z424C-TE).</div><div><br></div><div>[9] Digital Equipment Corp., 1986, Guide to VAX/VMS Disk and Magnetic</div><div> Tape Operations (Order no. AI-Y506B-TE).</div><div><br></div><div>[10] Digital Equipment Corp., 1986, VAX/VMS I/O User's Reference</div><div> Manual: Part I (Order no. AA-Z600C-TE).</div><div><br></div><div>[11] International Business Machines Corp., 1978, OS/VS Tape Labels</div><div> (Order No. GC26-3795-1).</div><div><br></div><div>Larry Baker<br>US Geological Survey<br>650-329-5608<br><a href="mailto:baker@usgs.gov">baker@usgs.gov</a><br></div></div></body></html>