I've got a 6 GB file, which needs to be copied to an USB-drive. The drive is 16 GB, but formatted in FAT so windows computers and Macs can read it. Fat limits the file size to 4 GB, so I cannot copy my file. My sollution would be to create a multi part archive, in two files of 3 GB.

How do I create a multi part archive on osx?


You can split any file with the split command:

split -b 2048m bigfile.tgz bigfile.tgz.

And you will get:


To combine them again:

cat bigfile.tgz.* > bigfile.tgz

It can also be used on Windows with copy /B

Of course, this is not really a multi-part archive, just cutting any file to pieces. Multi-part archives are usually aware that they are part nb 5 is a series, include CRC verification for each file etc. But that is specific to the archive format that you want to use.

  • Ok,this works. I was hoping for an archive file type the reciever can open in a GUI, like ZIP, RAR, etc. – Gerrit Aug 9 '10 at 14:20

Use programs like


To split with the internal zip command on OS X, type this in a terminal:

zip -s 1g BigFile6GB.zip BigFile6GB.iso

Where 1g = split files in 1GB of maximum size.

The result will be 6 files of 1GB each.

Read man zip on terminal to see others options of split size with the internal zip command.


There is a Mac-port of 7z archiver.

It can be used to make segmented archives.


Tar. Tar is a GNU-licensed tool capable of creating multi-volume archives. In Mac OS X you need to use the Terminal to access the command line.

On Mac OS X 10.4.11* it works as follows:

tar --tape-length=102400 -cMv --file=tar_archive.{tar,tar-{2..100}} [files to tar] 

102400 is size in KB or 100 MB. -c create, -M multi-volume and -v verbose. --file specifies the name of the tar archive to create, {tar,tar-{2..100}} is a bash expansion that provides the extensions .tar, .tar-2, .tar-3, etc. [files to tar] is the file or files to include in the archive.

Now, according to my source for this solution (http://hints.macworld.com/article.php?story=20090321124207437), the following is the extraction command, but, bash did not dutifully expand the braces for me so I had to develop a manual solution for combining the tar archives.

tar -xMv --file=tar_archive.{tar,tar-{2..100}} [files to extract] 

What worked for me was this:

tar -xMv --file=tar_archive.tar

Followed by the prompt:

Prepare volume #2 for `file_that_was_tarred' and hit return:

At this point, type:

n tar_archive.tar-2

Presumably this means `name of the next volume is tar-archive.tar-2'

Now you'll be prompted with:

Prepare volume #2 for `tar_archive.tar-2' and hit return: 

At this point press return.

You will need to repeat this process for each file in your multi-volume tar archive, remembering to change the suffix number each time.

Granted, there are much simpler ways now to accomplish this, but, I had to use Mac OS X 10.4.11 remotely using TeamViewer 7 (an amazing program that still runs and is allowed to access TeamViewer's servers on Mac OS X 10.4.11!!!). This was the least frustrating method of transferring a 2 GB disk image of a fresh install of Mac OS X 10.4.11 over the internet (if a 200 MB transfer fails that's 20 minutes, but, if a 2 GB transfer fails that's a day's worth of planning down the drain).

Source: http://hints.macworld.com/article.php?story=20090321124207437

*I'm providing tech support for my father who needs to use the Classic version of Word 5.0 which only runs in Mac OS X 10.4.11 (he has Alzheimer's which means he cannot learn new things and gets frustrated with new things). I live in a different city so the only way for me to help him is by remote control.

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