Create files of arbitrary size in Windows

fsutil file createnew FILENAME filesize(inbytes)
This command creates a file of arbitrary size in a windows environment.
Sample Output
fsutil file createnew deleteme 1024
File C:\deleteme is created

C:\>dir deleteme
Directory of C:\
02/05/2009  12:33 PM             1,024 deleteme
               1 File(s)          1,024 bytes
               0 Dir(s)   8,777,101,312 bytes free

By: archlich
2009-02-05 17:36:33

These Might Interest You

  • If you want to create fast a very big file for testing purposes and you do not care about its content, then you can use this command to create a file of arbitrary size within less than a second. Content of file will be all zero bytes. The trick is that the content is just not written to the disk, instead the space for it is somehow reserved on operating system level and file system level. It would be filled when first accessed/written (not sure about the mechanism that lies below, but it makes the file creation super fast). Instead of '1G' as in the example, you could use other modifiers like 200K for kilobytes (1024 bytes), 500M for megabytes (1024 * 1024 bytes), 20G for Gigabytes (1024*1024*1024 bytes), 30T for Terabytes (1024^4 bytes). Also P for Penta, etc... Command tested under Linux. Show Sample Output

    truncate --size 1G bigfile.txt
    ynedelchev · 2015-02-26 11:56:27 0
  • default stack size is 10M. This makes your multithread app filling rapidly your memory. on my PC I was able to create only 300thread with default stack size. Lower the default stack size to the one effectively used by your threads, let you create more. ex. putting 64k I was able to create more than 10.000threads. Obviously ...your thread shouldn't need more than 64k ram!!!

    ulimit -s 64
    ioggstream · 2009-08-06 10:40:25 0
  • Quickly create a new image with a certain size and background color.

    convert -size 100x100 xc:grey nopic100_100.jpg
    theduke · 2012-06-15 11:23:02 0
  • If you're trying to create a sparse file, you can use dd by 'skip'ing to the last block instance. ls -ls shows the actual size vs. the reported size Show Sample Output

    dd if=/dev/zero of=sparse_file bs=1024 skip=1024 count=1
    ubahmapk · 2010-10-24 00:28:34 1

What Others Think

nice, made me discover fsutil.
chickenkiller · 489 weeks and 2 days ago
When did windows become part of the Unix family?
ozymandias · 485 weeks and 4 days ago
Is this site only for Unix style commands?
jandro · 484 weeks and 6 days ago
Don't be a snob.
jandro · 484 weeks and 6 days ago
jandro, Yes, it is only for *the best Unix* commands. How am I being a snob to point out that this command is not appropriate?
ozymandias · 482 weeks and 2 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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