Re: tac replacement



On 11/26/2007 3:16 PM, Jürgen Kahrs wrote:
yiyu.jgl@xxxxxxxxx schrieb:


I need to process the end of a file before the beginning. I have seen
some threads where a tac | awk ... | tac solution is proposed, but
there is always the problem of not having tac in your system.


If you have a Unix sort command, then try this:

awk '{print NR, $0}' data_file.txt | sort -n -r | awk '{$1=""; print $0}'

That'll add a leading space and compress the rest of the spacing between fields.
If you really wanted to do that in awk|sort|awk, you'd do:

awk '{print NR, $0}' data_file.txt | sort -n -r | awk 'sub(/[[:digit:]]+ /,"")'

There are of course better UNIX tac-alternatives but that'd be best discussed in
comp.unix.shell....

Ed.

.

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