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From: Chris Angelico <rosuav@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: Mimick tac with python.
Date: Sat, 30 Jan 2016 15:56:17 +1100
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On Sat, Jan 30, 2016 at 3:46 PM, Hongyi Zhao <hongyi.zhao@gmail.com> wrote:
> I can use the following methods for mimicking tac command bellow:
>
> awk '{a[NR]=$0} END {while (NR) print a[NR--]}' input_file
> perl -e 'print reverse<>' input_file
>
> Is it possible to do the same thing with python?

python -c 'import sys; print("".join(list(open(sys.argv[1]))[::-1]))' input_file

Python doesn't have a short-hand for grabbing the file named as an
argument, but it's easy enough to reverse stuff.

ChrisA