home *** CD-ROM | disk | FTP | other *** search
- Path: sparky!uunet!uunet.ca!ecicrl!clewis
- From: clewis@ferret.ocunix.on.ca (Chris Lewis)
- Newsgroups: comp.mail.uucp
- Subject: Re: multi-hop uucp implies -C?
- Message-ID: <4114@ecicrl.ocunix.on.ca>
- Date: 10 Jan 93 05:22:36 GMT
- References: <1993Jan6.012324.18823@allegra.att.com> <6071@comton.airs.com>
- Organization: Elegant Communications Inc., Ottawa, Canada
- Lines: 57
-
- In article <6071@comton.airs.com> ian@airs.com (Ian Lance Taylor) writes:
- >mp@allegra.att.com (Mark Plotnick) writes:
-
- >>Under SunOS 4.1.1, "uucp x host1!host2!y" generates a command that
- >>starts with "uux -C". Is the "-C" really necessary? We have a user
- >>here who tried to send out 100 copies of a 6MB file via multi-hop uucp,
- >>and our disks didn't have anywhere near 600MB of space. Would it be OK
- >>if uucp gave uux the -C option only if uucp was itself given the -C
- >>option?
-
- >However, if you mean that the above uucp command somehow requested a
- >remote execution of ``uux -C'' on host1, then the -C is definitely
- >necessary. If uux on host1 was invoked without -C, then the file
- >would have to exist somewhere for uux to copy it. But if that were
- >the case, who would delete it?
-
- To make it abundantly more obvious: when the uuxqt used to invoke
- the "uux" on the remote system completes, it deletes all the data files
- associated with the job. If you didn't give the -C, the file would
- not be there to copy to the next machine when uucico gets around
- to try sending it. This is one of the first things people discover
- when they try to write uucp-style remote print programs...
-
- [Like the jackass ones stock on 3b1s. It uux's the request,
- then explicitly uucps the file across into public in a separate
- job. Turkeys. If uuxqt runs on the remote machine before the
- uucp completes (ie: you have multiple connects), the print fails because
- the file ain't there yet. 3b1 lp is thoroughly busted.]
-
- >>P.S. has there been any work toward implementing a sort of
- >>multicasting, in which a single uucp command line can specify that a
- >>file should be copied to multiple destinations? In the above case,
- >>virtually all the 100 copies were being sent to the same "host1", and it
- >>would be a win to just send the 6MB once and then have host1 execute a
- >>uucp command to send to the 100 destinations.
-
- >This would be fairly straightforward. You could make
- > uucp file --to host1!host3!file1 --to host1!host2!file2
- >execute the following on host1
- > uucp -C file --to host3!file1 --to host2!file2
- >Of course, the uucp running on host1 would have to recognize the --to
- >flag.
-
- There's several approaches that don't need modified uucps. Ie:
- "uuto" (uucp) the file into public on host1, then invoke a lot
- of these:
- uux host1!uucp public/file host2!...
- (with the appropriate quoting) Then you only have one copy, but it
- won't be automatically deleted.
-
- Or, write a shell script on host1 that does the multi-cast, and
- invoke that remotely. Still have the problem of deleting the file
- afterwards.
- --
- Chris Lewis; clewis@ferret.ocunix.on.ca; Phone: Canada 613 832-0541
- Psroff 3.0 info: psroff-request@ferret.ocunix.on.ca
- Ferret list: ferret-request@ferret.ocunix.on.ca
-