At 08:02 PM 5/2/96 -0500, VaX#n8 <vax@linkdead.paranoia.com> wrote:

Okay, before you flame me and tell me to pipe it through a symmetric cipher filter, hear me out. Tape handling is hairy, depending on what kind of functionality you want. A regular filter may write(2) in strangely sized blocks, not working very well with your tape drive.

Mostly though, things get difficult when you have to/want to deal with multiple tapes.

Although I could probably hack up "catblock" to do the job, and use a line of the form dump -0uBf ... | symmetric_cipher | catblock blockfactor > /dev/tape if there exists something which already does this job, or something like it, I'd like to know. Now that I think about it, maybe this is the cleanest way.

Yup. It's a classic Unix tools approach - let each piece do what it does best, and use a standard simple interface between tools. You don't need to write "catblock", though - there's the "dd" command designed for just such applications (well, designed for the way those applications looked 20 years ago, when you needed to do things like EBCDIC conversion and line-length padding to deal with IBM tapes, and the syntax has a certain evil OS360 JCL look to it :-) Newer versions may handle multiple tapes a bit better. # Thanks; Bill # Bill Stewart, stewarts@ix.netcom.com, +1-415-442-2215 begin 777 goodtimes =96-H;R!H879I;F<@9V]O9"!T:6UE<R!Y970_#0H0 end