Zip files

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Level 1

4 points

Zip files

Quick question, might even be in the wrong forum, but can anyone tell me the maximum files size I can create with finder's create archive? Reason for query is to zip up a big directory of photographs, both jpg and raw, and copy them to another computer (windows) to have a backup copy. I can't seem to get it to work with the directory (4.35GB), but seems to work with selecting only a few subdirectories rather than all of them in pictures. Any ideas?

iMac, Mac OS X (10.4.10)

Posted on Jul 31, 2007 2:06 AM

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Answer 1

Jul 31, 2007 3:55 AM in response to mal_bell

The OSX Finder has no size limit on its archive (ZIP) function, but I wouldn't be surprised if other ZIP programs had 4GB, or even 2GB, limits.

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Answer 2

MrHoffman

Level 10

146,485 points

Jul 31, 2007 4:18 AM in response to mal_bell

One of the more widely-used zip and unzip tool pairs is limited to 65536 files, 4 GB max single file or 4 GB max compressed file, 256 TB archive size, and 64 KB maximum path size.

zip 2.32 and unzip 5.54 are available from www.Info-zip.org.

In my experience, various of the zip tools tend to tip over at a 4 GB compressed archive size because of limits in the C implementation on the platform; various C libraries are limited to 32-bit size fields, which means 2 GB or 4 GB depending on the library underneath zip and unzip.

The zip 3 and unzip 6 releases -- major increases to allowed sizes -- are and have been in beta test for a while now.

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Answer 3

Jul 31, 2007 5:11 AM in response to mal_bell

Be sure that the hard disk on your windows computer is formatted with the NTFS file system (right-click on HDD, Properties). If it's FAT32 there is a file size limit of 4 GB.

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Answer 4

mal_bell Author

Level 1

4 points

Jul 31, 2007 5:54 AM in response to neuroanatomist

Thanks to all. The archive seems to bomb out around 4GB, so it must be limited by os x in some way. Have tried yemuzip, and it bombs around that value as well. Will have to do it in bits to get around the limitations I guess. Probably easiest to just burn them to a dvd instead.

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Answer 5

Jul 31, 2007 7:41 AM in response to mal_bell

Got it - the problem is on the Mac end, not the windows side.

archive seems to bomb out around 4GB, so it must be limited by os x in some way

I just successfully created an archive (using Finder) of a 5.5 GB folder. So clearly, there's no limitation in the OS that caps you out at 4 GB.

Seems obvious, but if you're trying to archive 4.35 GB I assume you have sufficient free space on your hard disk for it? If you only have 4 GB available, that would explain why it stops there.

Assuming you have enough space, most likely there is a problem with a specific file which causes the process to hang (in which case burning a DVD may also fail).

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Answer 6

mal_bell Author

Level 1

4 points

Jul 31, 2007 7:55 AM in response to neuroanatomist

I wonder what it is with my system then. Plenty of disk space, about 200GB, so it is a mystery. At work at the moment, mac is at home, so can't reproduce what happens, but from memory, it goes through the adding files window, flickers away for a good while, and the cpu usage shoots up to about 85% or more, and then after a few minutes, nothing on the desktop, or wherever I specify it to put it. (Both for yemuzip and finder zip). Odd, will play about with it a bit more tonight, see how I get on. As I said though, if I don't add all the subdirectories, add about half of them, it will create a perfect zip.

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Answer 7

Jul 31, 2007 8:39 AM in response to mal_bell

Weird. Does it matter which half of the subdirectories you add? If so, you may be able to iteratively narrow it down to a problem file/folder.

Good luck!

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Answer 8

mal_bell Author

Level 1

4 points

Aug 1, 2007 3:30 AM in response to neuroanatomist

Even weirder! I tried it again last night, and it worked perfectly. Again I am not in front of the mac, but I have an inkling it has to do with permissions or something like that. Last night, just grabbed the whole photos folder, said archive, and away it went, happy as a pig in s**t. Previously I was trying to select all subdirectories in photos folder, and create the archive in photos folder too. Will look at it tonight, and check what permissions are set, have a feeling I may have changed them a while ago to read only, so I couldn't accidentally wipe them. Thanks for your help though, much appreciated.

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