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Possible performance improvement (Bash and flat file)

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Special Forums UNIX and Linux Applications Infrastructure Monitoring Possible performance improvement (Bash and flat file)
# 8  
Old 05-11-2010
Furthermore:
Code:
echo "$stringa" >> "$proxyhistory"
echo "$stringb" >> "$proxyhistory"
echo "$stringc" >> "$proxyhistory"
echo "$stringd" >> "$proxyhistory"
echo "$stringe" >> "$proxyhistory"

can be done with

Code:
cat >> "$proxyhistory" <<EOF
$stringa
$stringb
$stringc
$stringd
$stringe
EOF

instead of running echo 5 separate times. Note that the last EOF must be at the START of the line and not indented.
Last edited by Corona688; 05-11-2010 at 05:11 PM..
# 9  
Old 05-11-2010
Thanks!

@Corona: I could use the 'split array' for retrieving a specific word from a string but for retrieving a substring, is there an alternative to
Code:
something=`echo $line | cut -d ' ' -f $start-$end`

# 10  
Old 05-11-2010
Quote:
Originally Posted by prafulnama
Thanks!

@Corona: I could use the 'split array' for retrieving a specific word from a string but for retrieving a substring, is there an alternative to
Code:
something=`echo $line | cut -d ' ' -f $start-$end`

A substring is
Code:
${VARNAME:START:LENGTH}

Expressions are allowed in there, so
Code:
${VARNAME:$START:((END-START))}
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