herber@bgsuvax.UUCP (Steve Herber) (10/15/85)
Has anyone modified 'tar' to handle and recover from tape errors? The 'Oh, I found an error and I quit' story is getting real old. If I don't hear from anyone else, I will see what I can do and post the diff's to the net. -- Steve Herber CSNET herber@bgsu.CSNET Sr. Systems Programmer UUCP ...!osu-eddie!bgsuvax!herber Bowling Green State Univ.
vsh@pixel.UUCP (vsh) (10/17/85)
> Has anyone modified 'tar' to handle and recover from tape errors? > The 'Oh, I found an error and I quit' story is getting real old. If > I don't hear from anyone else, I will see what I can do and post the > diff's to the net. I don't know if this will work for you, but ... On Pixel systems we use cartridge tapes, which behave as mag-tape look-alikes (or so it is claimed - I have never worked on a "big" machine with a real nine-track tape, so I have no basis for verifying this claim). Since /dev/rmt4 and /dev/rmt12 operate in non-rewind mode, we do: tar -xvf /dev/rmt4 wait for the tape read failure, then repeatedly do: tar -xvIf /dev/rmt4 Sooner or later (usually) the tape advances beyond the bad section and extraction of files resumes. We also use this technique to get to the end of a (new) archive and then extract from the tail end of an older archive: tar -tf /dev/rmt4 > /dev/null tar -xvIf /dev/rmt4 Good luck. -- Steve Harris Pixel Systems Inc.; 300 Wildwood St.; Woburn, MA. 01801 (617) 933-7735 x2314 (work) (617) 664-0099 (home) {allegra|ihnp4|cbosgd|ima|genrad|amd|harvard}!wjh12!pixel!vsh
nonh@utzoo.UUCP (Chris Robertson) (10/20/85)
In article <21@pixel.UUCP> vsh@pixel.UUCP (vsh) writes: >> Has anyone modified 'tar' to handle and recover from tape errors? > >I don't know if this will work for you, but ... >On Pixel systems we use cartridge tapes... <several commands> One note here -- Pixels have a very nice but non-standard 'tar'; several of the options including the -I option in the given command don't exist on many other systems. If anyone else wants them, I have a couple of small C programs written by Henry Spencer, designed to grab stuff from bad tar tapes -- they are known to work on both Pixel and V7 Unix. Send me mail; if enough arrives, and Henry agrees, I'll post them; otherwise, I'll mail them. --chris