blarson@dianne.usc.edu (bob larson) (02/03/90)
[inews here had some problems, sorry about the delay. Kim Kempf basicly said the same thing already.] Wolfgang Ocker and I seem to have different definitions of the term "hard link". In order to help clarify my posting, I'll give my definition: Hard link: A mechinism to get multiple names to one data file that does not give priority to any one name. There is only one copy of the data file actually present. In article <155400003@recco> weo@recco.chi.sub.org (Wolfgang Ocker) writes: > >Unfortunately hard links are nearly useless in the current version of >OSK RBF. I disagree. > It's impossible to remove (delete) a file (name) out of a >directory when a path is open on the file itself. True, but I fail to see the connection between this and hard links. In unix, you can create a file (leaving it open), delete it, write the file, then read it back in. The acutal contents of the file are present until the file is closed. In os9, you cannot delete an open file. While the unix concept is interesting and possibly useful, it does not (by my definition) have anything directly to do with hard links. >So this "feature" of >the RBF is only useful when "moving" files/directories around in the >directory structure and, of course, causing the same file to appear to be in several places at once, which is what hard links are. > (but it has nothing to do with UNIX hard links). ??? Hard links are useful wherever multiple names of a single file are needed. News (B, C, TMNN) uses this to avoid wasting disk space on cross-posted articles. >| Wolfgang Ocker | weo@recco.chi.sub.org | Ps: your posting software has a couple of bugs. My article I.D. was not present in the references line, and your Message-ID line was missing your domain. -- Bob Larson blarson@dianne.usc.edu usc!dianne!blarson --** To join Prime computer mailing list send mail to **--- info-prime-request@ais1.usc.edu or usc!ais1!info-prime-request
weo@recco.chi.sub.org (Wolfgang Ocker) (02/06/90)
> blarson@dianne.usc.edu (bob larson) writes ( 6:40 pm Feb 2, 1990 in recco:comp.os.os9): > Subject: Re: Hard links (was Re: More on 253 > Wolfgang Ocker and I seem to have different definitions of the term > "hard link". In order to help clarify my posting, I'll give my > definition: I admit that sometimes I have problems to express my thoughts, but I'm trying to improve my knowledge of the english language ... I don't think that we have a different definition of hardlinks. I wanted to point out that the 253 error problem becomes _really_ *obvious* and difficult when using hardlinks (pls. see my reply on Kim's article for another example.) It isn't transparent, neither for the user nor for a program, that he/it can't delete a file out of a directory when it is open by another (or the same) process. I don't think that hard links and the 253 error aren't related. It's a matter of the concept. When allowing different paths for one file we have to re-think what a directory entry is. At the moment a file and its entry in the directory(ies) are connected in a very strong manner (too strong in my opinion). > Hard links are useful wherever multiple names of a single file are needed. > News (B, C, TMNN) uses this to avoid wasting disk space on cross-posted > articles. YEP, that's the point! The expire program can't delete a file entry out of the directory comp/os/os9 when another user is reading an article in comp/sys/m68k which is a crossposting, by accident. > Ps: your posting software has a couple of bugs. My article I.D. was not > present in the references line, and your Message-ID line was missing your > domain. Thank you for the hint! I will try to fix this. (At the moment I'm happy to be able to post into the international news groups from my machine in the office ...) P.S.: I hope that I've expressed my opinion in a non-misunderstandable (does this word exist?) way. Thank you for your patience ... Yours, /// Wolfgang -- | Wolfgang Ocker | weo@recco.chi.sub.org | | Lochhauser Strasse 35a +-------------------------------+ | D-8039 Puchheim | reccoware systems | | Voice: +49 89 80 77 02 | | | Fax: +49 89 80 29 67 | Huh, What? Where am I? |