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Re^2: Unix rename behaviour

by ioannis (Prior)
on May 03, 2006 at 06:14 UTC ( #547073=note: print w/replies, xml ) Need Help??


in reply to Re: Unix rename behaviour
in thread Unix rename behaviour

True, but I think the OP meant "cp" and not "mv" when refering to the rename(?) command. Although the cp(1) command will create a new inode, the already opened filehandles are pointing to older inodes.

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Re^3: Unix rename behaviour
by Anonymous Monk on May 03, 2006 at 09:46 UTC
    Well, he meant "rename" when he said "rename"?! (it's linked to perl rename)

    -> Code should look like this

    $ cat foo.pl #!/usr/bin/perl -w ################## open(OUT,">testfileA"); print OUT "This is testfileA\n"; close(OUT); open(OUT,">testfileB"); print OUT "This is testfileB\n"; close(OUT); open(IN,"/tmp/testfileA"); rename ("testfileB", "testfileA"); print <IN>; close IN;

    Yields:
    $ ./foo.pl readline() on closed filehandle IN at ./foo.pl line 15.
    So the answer is "neither - rename closes the filehandle". I.
      So the answer is "neither - rename closes the filehandle".

      I think you missed the bit about "... two concurrent (Perl) processes ..." and "... when the second process next reads via it's open handle ..."

      A better test would be

      #!/usr/bin/perl use strict; use warnings; open OUT, '>', 'junk.1' or die $!; print OUT 'X'x 20 . "$_\n" for 1 .. 20; close OUT; open OUT, '>', 'junk.2' or die $!; print OUT 'Y'x 20 . "$_\n" for 1 .. 20; close OUT; open IO, '+<', 'junk.1' or die $!; seek IO, 0, 0; print scalar <IO>; system $^X, '-le', q[ print rename( 'junk.2', 'junk.1' ) ? 'worked' : +'failed']; print scalar <IO>; seek IO, 0, 0; print scalar <IO>; close IO; unlink 'junk.1';

      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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Discipulus manual work: i just tell the same to my boss: every time the quick solution is to assign some manual data entry task to my group.. because we have not direct access to many databases here..
[LanX]: point is: in high speed trade each bank has to remember what he has to get from the others... so dresdner got billed for losses but couldn't claim gains
Discipulus is this the IT?
[Corion]: Discipulus: Well, in many cases it doesn't make sense to build an interface and complicated program just to enter 20 rows into a database ;) But yes, automating data imports should pay off in the long run
[LanX]: Choroba: this happened before I joined, was still in uni, but my boss was summoned to the CEO of the second biggest German bank at that time and could only say " I told them its not ready" ;)
[LanX]: memories....I missed my connection while chatting
[Discipulus]: in this case Corion we are speaking about software licensing: evry year or two we must rescan the whole ced to produce an excel report, while at every activation / disactivation we update a black box DB: i said that i a week i can produce the perl to..
[Discipulus]: rend out the xls IF i have access to the DB
[choroba]: LanX I miss working in a bank sometimes...
[Corion]: Discipulus: Ooof. Especially yearly things are things I like to automate instead of trying to remember how I did things last year...

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