Here's an example of splitting a file using zip on Linux: zip -0 -s 3g out.zip foobar In that case, you should just split the file. This may be important if you don't have any "scratch space" to write the final file to. Of course, if you actually want to be able to work on the separate files, this doesn't work as well. Loose files may not look like a multipart file, especially if they lose their filenames somehow. (Not everyone knows how to cat files, but almost everyone can open a zip.) It's also very obvious that it's a multipart file, since the file is formatted as such. It also tends to be simpler for non-technical users. One big advantage to doing it this way is that the compression format acts as a wrapper, keeping you from accidentally doing anything with only one part of the file. I've used this technique myself to overcome the exact problem you're having. Combine the two, and you can split a file without wasting a bunch of time compressing it, especially if it's non-compressible data. Most of those same utilities also support splitting into multiple archives. When using such a mode, the compressed file simply acts as a container giving you the file-splitting ability, and the actual data is simply copied into the archive file, saving on processing time.Įxpanding on Michael's idea, many compression utilities/formats support a "store" mode, where they don't actually do any compression. File archivers also usually support a "store" or "no compression" mode which can be used if you know the contents of the file cannot be usefully further losslessly compressed, as is often the case with already compressed archives, movies, music and so on. Many file archivers also support splitting the file into multi-part archive files earlier, this was used to fit large archives onto floppy disks, but these days it can just as well be used to overcome maximum file size limitations like these. This can be used with any maximum file size limitation. To combine them, just use cat (con catenate): $ cat my6gbfile.part* > my6gbfile.recombinedĬonfirm that the two are identical: $ md5sum -binary my6gbfile my6gbfile.recombinedĥ8cf638a733f919007b4287cf5396d0c *my6gbfileĥ8cf638a733f919007b4287cf5396d0c *my6gbfile.recombined You can also, instead of -bytes=2GB, use -number=4 if you wish to split the file into four equally-sized chunks the size of each chunk in that case would be 1 610 612 736 bytes or about 1.6 GiB. (Just substitute your own.) Then, I split them into segments approximately 2 GiB in size each the last segment is smaller, but that does not present a problem in any situation I can come up with. Here, I use truncate to create a sparse file 6 GiB in size. My6gbfile my6gbfile.part00 my6gbfile.part01 $ split -bytes=2GB -numeric-suffixes my6gbfile my6gbfile.part For example, on Linux you can do something similar to: $ truncate -s 6G my6gbfile However, if you split the file into multiple files and recombine them later, that will allow you to transfer all of the data, just not as a single file (so you'll likely need to recombine the file before it is useful). So you cannot copy a file that is larger than 4 GiB to any plain FAT volume.ĮxFAT solves this by using a 64-bit field to store the file size but that doesn't really help you as it requires a reformat of the partition. The 4 GiB barrier is a hard limit of FAT: the file system uses a 32-bit field to store the file size in bytes, and 2^32 bytes = 4 GiB (actually, the real limit is 4 GiB minus one byte, or 4 294 967 295 bytes, because you can have files of zero length). Natively, you cannot store files larger than 4 GiB on a FAT file system.
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