Remove first N bytes and last N bytes from a binary file on AIX.


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# 1  
Remove first N bytes and last N bytes from a binary file on AIX.

Hi all,

Does anybody know or guide me on how to remove the first N bytes and the last N bytes from a binary file? Is there any AWK or SED or any command that I can use to achieve this?

Your help is greatly appreciated!!

Best Regards,
Naveen.
# 2  
If you are manipulating binary files, you cannot use awk or sed. Give a look at "dd" man page and try something like this:

Code:
dd if=input.bin of=output.bin bs=1 skip=X count=Y

Where X is the number of bytes you want to remove from the beginning, and Y is the number of bytes you want to process before the end of file.

Suppose you have a binary files which is 100 bytes in size and you want to remove the first 10 bytes and the last 5 bytes, obtaining an 85 bytes output.
The value of X will be 10, while the value of Y will be 85 (=100-10-5). You can find file size with a simple "ls" or "wc -c" command.
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