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Top Forums UNIX for Advanced & Expert Users How to prevent grep command from throwing a system trap if No match is found. Post 302274821 by methyl on Thursday 8th of January 2009 12:42:20 PM
Old 01-08-2009
I agree with yegolev. Using trap in this way is unusual. ERR is only triggered if the last command in a pipeline fails. Also your script probably needs to append to the log rather than overwrite it. Here is an example:

#!/bin/ksh
trap 'echo "Trap fired";exit' ERR
ls server* 2>/dev/null 1>/dev/null # Fire trap if file is missing
#
(
ls server* | while read filename
do
grep "ABC" "${filename}"
done
) 2>&1 >> logfile.log
 

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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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