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Top Forums Shell Programming and Scripting Bash : More parameter expansion and IFS Post 303018416 by MadeInGermany on Tuesday 5th of June 2018 03:22:37 PM
Old 06-05-2018
If I see many if [[ $var in a row then it's time to think of a case-esac.
But it uses a whole line glob match, not a regular expression.
Here a leading and trailing * allow preceding and succeeding characters (while a regular expression does not need leading/trailing .*)
Code:
while read line
do
  case $line in
  (*sysName*) sysN=${line##* } ;;
  (*sysObjectID*) sysO=${line##*.} ;;
  (*sysDescr*) TMP=${line##*Version }; sysD=${TMP%% RELEASE*} ;;
  esac
done < <($SNMPG $RW -v2c -mALL $i sysDescr.0 sysName.0 sysObjectID.0 2>/dev/null)
printf "%s,%s,%s\n" "$sysN" "$sysD" "$sysO"

I also replaced the "herestring made of a command substitution" <<< $( ) by a "process substitution" < <( ).
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textutil::trim(n)				    Text and string utilities, macro processing 				 textutil::trim(n)

__________________________________________________________________________________________________________________________________________________

NAME
textutil::trim - Procedures to trim strings SYNOPSIS
package require Tcl 8.2 package require textutil::trim ?0.7? ::textutil::trim::trim string ?regexp? ::textutil::trim::trimleft string ?regexp? ::textutil::trim::trimright string ?regexp? ::textutil::trim::trimPrefix string prefix ::textutil::trim::trimEmptyHeading string _________________________________________________________________ DESCRIPTION
The package textutil::trim provides commands that trim strings using arbitrary regular expressions. The complete set of procedures is described below. ::textutil::trim::trim string ?regexp? Remove in string any leading and trailing substring according to the regular expression regexp and return the result as a new string. This is done for all lines in the string, that is any substring between 2 newline chars, or between the beginning of the string and a newline, or between a newline and the end of the string, or, if the string contain no newline, between the beginning and the end of the string. The regular expression regexp defaults to "[ \t]+". ::textutil::trim::trimleft string ?regexp? Remove in string any leading substring according to the regular expression regexp and return the result as a new string. This apply on any line in the string, that is any substring between 2 newline chars, or between the beginning of the string and a newline, or between a newline and the end of the string, or, if the string contain no newline, between the beginning and the end of the string. The regular expression regexp defaults to "[ \t]+". ::textutil::trim::trimright string ?regexp? Remove in string any trailing substring according to the regular expression regexp and return the result as a new string. This apply on any line in the string, that is any substring between 2 newline chars, or between the beginning of the string and a newline, or between a newline and the end of the string, or, if the string contain no newline, between the beginning and the end of the string. The regular expression regexp defaults to "[ \t]+". ::textutil::trim::trimPrefix string prefix Removes the prefix from the beginning of string and returns the result. The string is left unchanged if it doesn't have prefix at its beginning. ::textutil::trim::trimEmptyHeading string Looks for empty lines (including lines consisting of only whitespace) at the beginning of the string and removes it. The modified string is returned as the result of the command. BUGS, IDEAS, FEEDBACK This document, and the package it describes, will undoubtedly contain bugs and other problems. Please report such in the category textutil of the Tcllib SF Trackers [http://sourceforge.net/tracker/?group_id=12883]. Please also report any ideas for enhancements you may have for either package and/or documentation. SEE ALSO
regexp(n), split(n), string(n) KEYWORDS
prefix, regular expression, string, trimming CATEGORY
Text processing textutil 0.7 textutil::trim(n)
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