in reply to unable to extract same file twice using Archive::Zip

Your explanation of WHY you need to extract a particular file (or files) a second time fails the "plausibility test" with me... and your simplified example below casts no light on the problem (largely because I can see no rational justification for dividing what sounds like a merely occasional and low-overhead procedure among multiple servers (unless, perhaps, one is a db server?).

Worse, your simplified code gives no hint of HOW you attempt to unzip a member a second time, nor of HOW you're directing the second attempt to a different directory (to avoid overwriting the first) and nowhere do you cite error messages supporting your description of what's happening. Please clarify.

See I know what I mean. Why don't you?. The OP, in fact, sounds like you believe there's some sort of quantum entanglement between the files... or "spooky action at a distance."

If not, why can't you...

or, better, provide a clearer explanation -- with code -- of what you're trying to do.

If you believe the issue is in your module, the first alternative above would offer you -- at a minimum -- the opportunity to start testing your belief)

OT: Your " <<quote>" pseudo-tags are not particularly prominent. You may want to see Markup in the Monastery, Writeup Formatting Tips and Perl Monks Approved HTML tags. And, as my usage in this para suggests, one common (local) way of making quotes obvious here is to use italics... or, in the case of a long-ish quote, to use italics inside a <blockquote>...</blockquote> pair.

  • Comment on Re: unable to extract same file twice using Archive::Zip

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Re^2: unable to extract same file twice using Archive::Zip
by Pickwick (Beadle) on Jul 06, 2010 at 14:45 UTC
    Your explanation of WHY you need to extract a particular file (or files) a second time fails the "plausibility test" with me...

    Maybe I should have been more careful with my question because it's not, that I want to discuss why I have to keep the processing order or why there's even the need to do the processing twice on server and client. I really just wanted to know if one and the same zip member can be extracted more than once. And with one and the same I mean the same object, no zip reloading, nothing.

    Worse, your simplified code gives no hint of HOW you attempt to unzip a member a second time,

    Of course it does, I have a zip member on which extractToFileNamed is called twice and the second call fails.

    nor of HOW you're directing the second attempt to a different directory (to avoid overwriting the first)

    extractToFileNamed gets a temporary filename each time it's called from File::Temp::tempnam.

    nowhere do you cite error messages supporting your description of what's happening

    The error is AZ_STREAM_END as said before, but I don't understand why. The temporary file is created properly, it just gets no data.

    use a standalone zip program?

    Why should I day? Archive::Zip is the better tool for my needs.

    copy the extracted file(s) that need dupes?

    It's no problem to find another approach, I just wondered why something that easy like extracting a zip member object twice caused me trouble.

    Close the zip and reopen for your second attempt?

    Of course I can do that, and I do it now, but why should this be neccessary? The member class doesn't say something about that extracting more than once kills people.

    If you believe the issue is in your module

    Of course I don't. ;-)

[reply]
      I stand corrected re the multiple extractions. Your simplified code does attempt to do so.

      re 'error messages' however, I still don't see them. Executing perldoc Archive::Zip will tell you:

       ERROR CODES
    Many of the methods in Archive::Zip return error codes. These are
    implemented as inline subroutines, using the "use constant" pragma
+. They
    can be imported into your namespace using the ":ERROR_CODES" tag:

      use Archive::Zip qw( :ERROR_CODES );

      ...

      unless ( $zip->read( 'myfile.zip' ) == AZ_OK ) {
          die "whoops!";
      }

    AZ_OK (0)
        Everything is fine.

    AZ_STREAM_END (1)
        The read stream (or central directory) ended normally.

    AZ_ERROR (2)
        There was some generic kind of error.

    AZ_FORMAT_ERROR (3)
        There is a format error in a ZIP file being read.

    AZ_IO_ERROR (4)
        There was an IO error.

      [download]

      The only one of these you cite is "AZ_STREAM_END" which does NOT indicate an error; far less, what kind of error.

      However, attempting to execute you alternate code (under w2k with A::Z v130 on perl 5.8 with strict and warnings; do you use these pragmas?) does pop up a message:

      Can't locate object method "extractToFileNames" via package "Archive::Zip::ZipFileMember" at 848152.pl line 13.

      And the meaning of your reply re suspecting the module boils down to interpretation of the wink? Perhaps you should consult the author, Adam Kennedy... but with better evidence than a wink.

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