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How to reverse the contents of a file?

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# 8  
Old 06-05-2007
attached is a compilation of different methods.
Last edited by vgersh99; 03-04-2010 at 01:54 PM..
# 9  
Old 06-06-2007
Quote:
Originally Posted by aajan
Hi Guys,
Am new to this forum .... And also to shell scripting

I need a k-shell script to reverse the contents of a file...

Please come up with the solutions...

With regards,
Anand
By reverse, you mean character by character or line by line?
# 10  
Old 05-16-2008
Try playing with the -r flag on tail.
# 11  
Old 05-17-2008
Just out of curiosity, you can use shell constructs for this, too.

Code:
#!/bin/sh

tac () {
  local line
  if read line; then
    tac
    printf '%s\n' "$line"
  fi
}

for f; do
  tac <"$f"
done

ksh could use print instead of printf; tested with bash. (Using echo is not very robust, but would be compatible even with the earliest Bourne shells. But then, local is a fairly recent addition, isn't it?)
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