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Top Forums UNIX for Dummies Questions & Answers Reversing line and word order using awk Post 302506642 by jim mcnamara on Monday 21st of March 2011 12:48:39 PM
Old 03-21-2011
This sounds a lot like homework. We have a special forum for homework.
You can use the tac command if you are on linux.
Code:
tac filename | awk 'your code goes here'

Otherwise:
Code:
awk ' arr[NR]=$0; END{for(i=NR; i>0;i--) {print arr[i]}}' filename

acts like tac.
SO:
[code]
awk ' arr[NR]=sprintf("%s %s %s", $3 , $2, $1); END{for(i=NR; i>0;i--) {print arr[i]}}' filename

This works for a fixed number of fields in the file.
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TAC(1)								   User Commands							    TAC(1)

NAME
tac - concatenate and print files in reverse SYNOPSIS
tac [OPTION]... [FILE]... DESCRIPTION
Write each FILE to standard output, last line first. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -b, --before attach the separator before instead of after -r, --regex interpret the separator as a regular expression -s, --separator=STRING use STRING as the separator instead of newline --help display this help and exit --version output version information and exit AUTHOR
Written by Jay Lepreau and David MacKenzie. REPORTING BUGS
Report tac bugs to bug-coreutils@gnu.org GNU coreutils home page: <http://www.gnu.org/software/coreutils/> General help using GNU software: <http://www.gnu.org/gethelp/> Report tac translation bugs to <http://translationproject.org/team/> COPYRIGHT
Copyright (C) 2010 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO
rev(1). The full documentation for tac is maintained as a Texinfo manual. If the info and tac programs are properly installed at your site, the command info coreutils 'tac invocation' should give you access to the complete manual. GNU coreutils 8.5 February 2011 TAC(1)
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