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insert null in unix files

 
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# 1  
Old 02-12-2008
insert null in unix files
Hi everybody,

How to add null values in unix file?

This is what was asked to me in an interview.
# 2  
Old 02-12-2008
maybe:

cat /dev/zero > test.txt

or

cat /dev/null > test.txt

??


Quote:
Originally Posted by sachin.gangadha
Hi everybody,

How to add null values in unix file?

This is what was asked to me in an interview.
# 3  
Old 02-12-2008
Appending nul characters in UNIX
Quote:
Originally Posted by sachin.gangadha
Hi everybody,

How to add null values in unix file?

This is what was asked to me in an interview.
The previous poster should have said (for SH shells)

Code:
dd if=/dev/zero bs=1 count=<count> >> outfile.txt

Because you want to append some zero values. Cat'ing from /dev/null will give you nothing.

The other way, is if in you're vi/m, you can hit CTRL-V CTRL-@ to get a NUL character. You can also use perl to generate one.
# 4  
Old 02-12-2008
thanks for the reply.

I am not getting what you guys have explained probably bcoz i am jst a beginner.

Once again i am making my question clear. how to add null value to a file?

just wanna create a file with nulls. i dont know whether you can do this unix that is why i need experts like you guyz to answer.
# 5  
Old 02-13-2008
What do you mean by "adding null values to a file" ? What's the required output ?
 
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