#830 Duplicate filename error appears exactly at 2nd update

[agromsl]

under Windows XP, with 7-zip 4.57
using this command line:
7Z u -tzip -mx=8 -r "test.zip" "que_jai_bousille\*"

when the follwing file is in the «que_jai_bousille» directory:
Entreprises_Membres_CCSOP–Partenaires_développement_local.doc

First run creates the test.zip file,
second run updates the zip file, even if the file was not modified in the mean time
third run generates a «duplicate filename» error, with the file to compress still not modified since the first run.

See the output of the 3 runs of the same command line:
- - - - - - - - - - - - - - - - - - - - - - - - - - -
C:\_jt>7Z u -tzip -mx=8 -r "test.zip" "que_jai_bousille\*"

7-Zip 4.47 beta Copyright (c) 1999-2007 Igor Pavlov 2007-05-27
Scanning

Creating archive test.zip

Compressing que_jai_bousille\Entreprises_Membres_CCSOP-Partenaires_développemen
t_local.doc

Everything is Ok

C:\_jt>7Z u -tzip -mx=8 -r "test.zip" "que_jai_bousille\*"

7-Zip 4.47 beta Copyright (c) 1999-2007 Igor Pavlov 2007-05-27

Scanning

Updating archive test.zip

Compressing que_jai_bousille\Entreprises_Membres_CCSOP-Partenaires_développemen
t_local.doc

Everything is Ok

C:\_jt>7Z u -tzip -mx=8 -r "test.zip" "que_jai_bousille\*"

7-Zip 4.47 beta Copyright (c) 1999-2007 Igor Pavlov 2007-05-27

Scanning

Updating archive test.zip

Error:
Duplicate filename:
que_jai_bousille\Entreprises_Membres_CCSOP-Partenaires_développement_local.doc
que_jai_bousille\Entreprises_Membres_CCSOP-Partenaires_développement_local.doc
- - - - - - - - - - - - - - - - - - - - - - - - - - -

When I use a directory with thousands of files, only this file bugs, the critical character in the filename is the dash, that is not the one in lower ascii (#45) but another one with a higher character number (don't know if it is #150, 151 or 173). If I retype the filename with the lower ascii dash (#45), then the bug does not show anymore.

I can't control the use of such non standard characters in filenames, so I can't rely on 7-zip in backup routines (with batch files) because it is only after 3 runs (very long runs when enormous amount of files to backup) of a batch files that a bug will finally show up!

Only work around found is to destroy the file to force its regeneration after the 2nd update, which makes every forth backup extremely long!

[agromsl]

in a directory to backup, will generate duplicate filename error, only at the 3rd run of the 7z command line

[Igor Pavlov]

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Try 7-Zip 4.58 beta.

[agromsl]

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I just tried 4.58 beta with the same unmodified file and directory sample.

The problem is still the same. First run creates, second updates and third bugs.

Thank You!

P.S. some additional informations. I had already made sure my sample file was not corrupted. I also made sure that the content of the file had nothing to do with the bug by modifying the content without changing the name of the file, before deleting the zip file and then retrying the command line, 3 times...

[Igor Pavlov]

Logged In: YES
user_id=65083
Originator: NO

Yes, probably there are problems with some cases. I'm thinking how to fix it.
You can try to use Unicode encoding with 7-Zip 4.58:
1) .7z format with -ms- switch
2) .zip format with -mcu switch

[agromsl]

Because I had eradicated all filenames including the critical characters, I could live with the bug for a few times. But today, I met some new files containing some of those.

I assumed version 4.60beta would have the same functionalities required by the option number 2 in your previous message.

I tried the -mcu switch (I generate zip files) and it could deal with the problematic character (alt-0146, under windows file system, a kind of apostrophe, «’») in file names, even at 4th, 5th, 6th... upgrade of the same zip file.

Only precaution, old winzip versions can't decode those filename appropriately:
«L’Archive.doc» is stored as «LÔÇÖArchive.doc».
But I have no problem restoring the file with its original filename if I extract it with 7-zip.

Of course, I had previously tested the compression with version 4.57 and without the -mcu switch, to make sure the «’» was in fact causing the problem!

That resolves a very preoccupying problem.

Thank You very much!