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Top Forums Shell Programming and Scripting Sed/grep: check if line exists, if not add line? Post 303013274 by RudiC on Monday 19th of February 2018 05:13:42 AM
Old 02-19-2018
Speeding up could be done by NOT executing a bash shell with command / function for every single file name found. Have find write all file names to a temp file, and read that in a while loop, callig the function from within - if a function is needed at all. grepping and sedding the same file means read / process it twice - use sed only to process it once. And, on top of what MadeInGermany already stated, you need to specify the position where to add the addstring if searchstring is missing, unless that were end-of-file.
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ZGREP(1)						      General Commands Manual							  ZGREP(1)

NAME
zgrep - search possibly compressed files for a regular expression SYNOPSIS
zgrep [ grep_options ] [ -e ] pattern filename... DESCRIPTION
Zgrep invokes grep on compressed or gzipped files. These grep options will cause zgrep to terminate with an error code: (-[drRzZ]|--di*|--exc*|--inc*|--rec*|--nu*). All other options specified are passed directly to grep. If no file is specified, then the standard input is decompressed if necessary and fed to grep. Otherwise the given files are uncompressed if necessary and fed to grep. If the GREP environment variable is set, zgrep uses it as the grep program to be invoked. EXIT CODE
2 - An option that is not supported was specified. AUTHOR
Charles Levert (charles@comm.polymtl.ca) SEE ALSO
grep(1), gzexe(1), gzip(1), zdiff(1), zforce(1), zmore(1), znew(1) ZGREP(1)
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