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If grep value is null then assign 0 to variable

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# 8  
Old 09-18-2014
The following works with all Posix shells
Code:
ins=0
del=0
upd=0
a_i=0
set -f
while read line
do
  set -- $line
  eval lastA=\$$#
  case `echo "$line" | tr '[:lower:]' '[:upper:]'` in
  INSERT*) ((ins=ins+lastA));;
  DELETE*) ((del=del+lastA));;
  UPDATE*) ((upd=upd+lastA));;
  "AFTER IMAGES"*) ((a_i=a_i+lastA));;
  esac
done <"$logfile1"
set +f
echo "INSERT=$ins"
echo "DELETE=$del"
echo "UPDATE=$upd"
echo "AFTER_IMAGES=$a_i"

# 9  
Old 09-18-2014
Quote:
Originally Posted by MadeInGermany
The following works with all Posix shells
Code:
ins=0
del=0
upd=0
a_i=0
set -f
while read line
do
  set -- $line
  eval lastA=\$$#
  case `echo "$line" | tr '[:lower:]' '[:upper:]'` in
  INSERT*) ((ins=ins+lastA));;
  DELETE*) ((del=del+lastA));;
  UPDATE*) ((upd=upd+lastA));;
  "AFTER IMAGES"*) ((a_i=a_i+lastA));;
  esac
done <"$logfile1"
set +f
echo "INSERT=$ins"
echo "DELETE=$del"
echo "UPDATE=$upd"
echo "AFTER_IMAGES=$a_i"

Actually, you need some extensions to POSIX requirements to process the above script. The current standard specifies the behavior of $((expression)), but not the behavior of ((expression)). (ksh88 does not support ((expression)).)

To be portable to any POSIX shell, lines like:
Code:
  INSERT*) ((ins=ins+lastA));;

would have to change to something like:
Code:
  INSERT*) ins=$((ins+lastA));;

This User Gave Thanks to Don Cragun For This Post:
MadeInGermany
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