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creating file of 1MB using shell command?

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# 1  
Old 03-29-2006
creating file of 1MB using shell command?
Hi everybody in the forum,

I want to create an empty file of say some 1MB ,i mean at the command line itself.How is this possible??????EEK!
# 2  
Old 03-29-2006
Try this.

Code:
dd if=/dev/zero of=output.file bs=1024 count=1024

It will be filled with /dev/zero's
# 3  
Old 04-04-2006
Explaination clearly....
Hi Thanks for the reply....
I would like to be explained in detail
# 4  
Old 04-04-2006
Look into man dd. Or better yet info dd
# 5  
Old 04-04-2006
Quote:
Originally Posted by vino
Try this.

Code:
dd if=/dev/zero of=output.file bs=1024 count=1024

It will be filled with /dev/zero's
this is just a suggestion,
when generating files of huge size,
it is better you attack from the block size thereby reducing the count

for a 1 MB file,
Code:
dd if=/dev/zero of=output.file bs=1024 count=1024

time taken = 0.13 s
Code:
dd if=/dev/zero of=output.file bs=1048576 count=1

time taken = 0.08 s
it is just a difference of (0.13 - 0.08) s

but consider generating some 200 MB files
attacking block size would surely provide a difference.
Last edited by Yogesh Sawant; 02-26-2010 at 02:39 PM.. Reason: added code tags
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