IDEA: Large file generator

[Sentinel]

I would like a simple little utility for creating large test files rather like 'bigfile' under UNIX.

Basically all that should be required is to give the path/filename of the file to create, the file size in bytes/kb/mb etc and the byte to fill the file with from 0-255 (or 00-FF hex).

I have an old DOS utility which does a similar thing but DOS has a few size limitations so a native Windows utility would be great.

[mouser]

skrommel - before you start!!! -> i know this must exist several times over in freeware land.

[Sentinel]

Yeah, that's what I thought but I've not been having much luck finding one that allows the creation of files with a given binary value.  Here is one that is close, but no cigar: -

http://www.programme...e16/cat288/37062.htm

It seems to only allow creation of files with ASCII characters and only lets you input the file length in bytes, not bytes/kb/mb/gb.  If someone does know of such a tool I'd be interested. 

[mouser]

good point - it's easy enough to write that if you have some odd requirements regarding the bytevalue you want and the size in nice format, then its a tiny enough request to warrant writing.

i'll write this for ya if for some reason the heavens crash down and skrommel doesn't want to

[skrommel]

  AutoHotkey really isn't up for this task,  being without binary file support, and as a script language it's quite slow, but here goes a version with code stolen from Chris at the AutoHotkey forum.

BigByte - Create accurately sized files.

Feautures:
- Very slow on big files! Much faster on big files!
- Create binary or ascii files.



You'll find the downloads and more info at Skrommel Software.

Skrommel

[mouser]

yeah actually i was thinking after i posted that this isnt really a job perfect for autohotkey -
it's a good lesson regarding the right tools for the right job - ahk does some very hard stuff so easily, and yet for something like this its just not particularly well suited.

[mouser]

as a side note: skrommel beware you don't burn out!
all of us programmers have to pace ourselves - so feel free to ignore some requests

[mouser]

btw -
this would be a *perfect* programming assignment for someone who is just getting learning programming and wants a little manageble project to try to complete.

[skrommel]

  And then there's the odd stroke of inspiration...
 
Check out BigByte v1.1!

With a little help from DOS it will fill your harddisk a lot quicker! So be careful! It creates a 1 byte file and doubles it until it's big enough, then copies the needed files together and deletes the rest.

You'll find the downloads and more info at Skrommel Software.

Skrommel

[seedling]

how about this

oops! just a minor error... like it didn't write the file!

fixed now

[mouser]

looks like its working great!

seedling, may i put your submission on the coding snacks page here for permanent download: https://www.donation...dingSnacks/index.php

[mouser]

DFC has now been added to the coding snacks section:
https://www.donation...dingSnacks/index.php

[Sentinel]

Thanks for all the hard work guys!  It is really appreciated. 

[Edvard]

Here's another way, using Sysinternals' wonderful Contig

from the website:

...
 To make a new file that is defragmented upon creation, use Contig like this:

Usage: contig [-v] [-n filename length]

[lanux128]

in WinXP, one can create large files files with the fsutil utility.

Syntax: fsutil file createnew <filename> <length>

[Rekrul]

And then there's the odd stroke of inspiration...
 
Check out BigByte v1.1!

With a little help from DOS it will fill your harddisk a lot quicker! So be careful! It creates a 1 byte file and doubles it until it's big enough, then copies the needed files together and deletes the rest.

-skrommel (September 27, 2005, 09:39 PM)

Just tried this on my old Windows 98SE system (there were no requirements listed, which is generally understood to mean that it works on all versions of Windows) and got the following error when I asked it to create a 20MB file;

IDEA: Large file generator

[f0dder]

Rekrul: seems that the script is pretty NT focused - NT has cmd.exe as shell, whereas Win9x has command.com . The script seems like a pretty damn bad way of generating big files anyway