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Top Forums Shell Programming and Scripting Removing all lines prior to the last pattern in a file/stream Post 302503785 by mirni on Friday 11th of March 2011 04:30:50 PM
Old 03-11-2011
My solution would be to scan the output twice -- so that I can identify which pattern is the last one. Something like this:
Code:
lastOccur=`sed -n '/pattern/=' output | tail -1` #will output line numbers matching pattern
sed -n "$lastOccur,$ p" output

---------- Post updated at 11:30 AM ---------- Previous update was at 11:27 AM ----------

Ahhh... 'tac' ... nice one. Then you can do:

Code:
tac output | sed  "/pattern/,$ d" | tac

 

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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
GNU coreutils online help: <http://www.gnu.org/software/coreutils/> Report tac translation bugs to <http://translationproject.org/team/> COPYRIGHT
Copyright (C) 2017 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) Full documentation at: <http://www.gnu.org/software/coreutils/tac> or available locally via: info '(coreutils) tac invocation' GNU coreutils 8.28 January 2018 TAC(1)
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