roy@phri.UUCP (Roy Smith) (05/18/85)
1) If you have 4.2bsd, you have "arff". Console media on 780s (and 750s?) are in RT-11 format. Arff is for building new boot floppies, but handles other RT-11 disk images, too. Thanks to Scott Bradner <sob@talcott.UUCP> for pointing this out. 2) There is a program called rtpip which deals with RT-11 file systems. I was offered a copy by Sohail Hussain <sohail@terak.UUCP>; presumably if you need it, you can get it from him. 3) Geoff Collyer <geoff@utcsstat.UUCP> sent me versions of rtpip, rtio, and rtdir. Says Geoff, "[...] ran at one time on v6 on the PDP-11 [...] a good chance that on the VAX you'll have to change a lot of [...] int's to [...] short's". 4) There is some confusion about RT-11 disks and tapes; they are NOT the same format. Disks (i.e. file system images, regardless of the physical media) can be read using one of the above programs. Tapes are (I think) in a format called files-11 (the same format as VMS COPY tapes?), and can be read by a variety of programs floating around the net (ansitar, f11r). I have f11r, if anybody wants it. 5) In an emergency, you can use a procedure I worked out a while ago. Since RT-11 files are stored in ascii in contiguous blocks, if you know what is (or might be) in the file you want, use "grep -b" to find one of the blocks in the file, then use "dd" to pull off the surrounding bunch of blocks and trim away the extra. Remember to strip of the trailing nulls in the last block (just reading and writing the file with ed works). -- allegra!phri!roy (Roy Smith) System Administrator, Public Health Research Institute
cdl@mplvax.UUCP (Carl Lowenstein) (05/22/85)
In article <234@phri.UUCP> roy@phri.UUCP (Roy Smith) writes: > 1) If you have 4.2bsd, you have "arff". Console media on 780s >(and 750s?) are in RT-11 format. > 2) There is a program called rtpip which deals with RT-11 file >systems. > 4) There is some confusion about RT-11 disks and tapes; they are >NOT the same format. Disks (i.e. file system images, regardless of the >physical media) can be read using one of the above programs. Tapes are >(I think) in a format called files-11 (the same format as VMS COPY >tapes?), and can be read by a variety of programs floating around the >net (ansitar, f11r). Just a few more comments: 1) and 2) above are fine as long as the RT-11 disk doesn't have very many files on it. "arff" does not claim to cope with an RT-11 directory of more than one segment (72 files max). "rtpip" thinks it knows about multi-segment directories, but as I remember, it is wrong, because the directory segments are chained, not sequential. It is likely that either of these programs might need tweaking to keep up with minor variations in RT-11 directory structure since V2c (we're now up to V5.1c). As to 4), RT-11 tapes are (sub)ANSI-standard. They are single volumes, and the label records are 512 bytes long rather than the usual 80. Also all the data records are 512 bytes. Ansitar works fine, as long as nobody has forgotten that the 'R' switch implies 512-byte records. -- carl lowenstein marine physical lab u.c. san diego {ihnp4|decvax|akgua|dcdwest|ucbvax} !sdcsvax!mplvax!cdl