Nagios Log Monitoring(line by line) Plugin for linux

#!/bin/bash
#Purpose         : To monitor the log line by line
#Authors         : Ranjith Kumar R
#Date            : 29th March 2014
#Version         : V2.0

PROGNAME=`/bin/basename $0`
PROGPATH=`echo $0 | sed -e 's,[\\/][^\\/][^\\/]*$,,'`
REVISION="V1.0"
ECHO="/bin/echo"
STATE_UNKNOWN=3
STATE_OK=0
STATE_CRITICAL=2
TAIL="/usr/bin/tail"
MAIL="/bin/mail"
PRINT="/usr/bin/printf"
DATE=`/bin/date`
CONTACTEMAIL="ranjith@test.com"
print_usage() {
    echo "Usage: $PROGNAME -F LOGFILEPATH -q query -c critical count of string match"
    echo "Usage: $PROGNAME --help"
    echo "Usage: $PROGNAME --version"
}
print_help() {
    print_revision $PROGNAME $REVISION
    echo ""
    print_usage
    echo ""
    echo "Log file pattern detector plugin for Nagios"
    echo ""
    support
}
# Make sure the correct number of command line
# arguments have been supplied
if [ $# -lt 6 ]; then
    print_usage
    exit $STATE_UNKNOWN
fi
# Grab the command line arguments
#LOGFILEPATH=$1
#query=$2
exitstatus=$STATE_WARNING #default
while test -n "$1"; do
    case "$1" in
        --help)
            print_help
            exit $STATE_OK
            ;;
        -h)
            print_help
            exit $STATE_OK
            ;;
        --version)
            print_revision $PROGNAME $REVISION
            exit $STATE_OK
            ;;
        -V)
            print_revision $PROGNAME $REVISION
            exit $STATE_OK
            ;;
        --filename)
            LOGFILEPATH=$2
            shift
            ;;
        -F)
            LOGFILEPATH=$2
            shift
            ;;
        --query)
            query=$2
            shift
            ;;
        -q)
            query=$2
            shift
            ;;
        --critical)
            critical=$2
            shift
            ;;
        -c)
            critical=$2
            shift
            ;;
        -x)
            exitstatus=$2
            shift
            ;;
        --exitstatus)
            exitstatus=$2
            shift
            ;;
        *)
            echo "Unknown argument: $1"
            print_usage
            exit $STATE_UNKNOWN
            ;;
    esac
    shift
done
if [ -r $LOGFILEPATH ]; then

echo "$LOGFILEPATH has read permission" > /dev/null

else

echo "Nagios unable to read $LOGFILEPATH file, please check the file permission"

exitstatus=$STATE_CRITICAL
        exit $exitstatus

fi

query1=`echo $LOGFILEPATH |  awk -F"/" '{print $NF}'`.`echo $query | awk '{print $1}'`

                if [ -f "/usr/local/nagios/libexec/lastline.$query1" ]; then
                count=0
                else
                echo 0 > /usr/local/nagios/libexec/lastline.$query1
                fi
COUNT=0
LA="/usr/local/nagios/libexec/lastline.$query1"
LASTLINE=`cat /usr/local/nagios/libexec/lastline.$query1`
NEWLINE=`cat $LOGFILEPATH | wc -l`
if [ "$NEWLINE" -lt "$LASTLINE" ];then
echo 0 > /usr/local/nagios/libexec/lastline.$query1
fi
if [ "$NEWLINE" -gt "$LASTLINE" ];then
LINE=$(expr $NEWLINE - $LASTLINE)
echo $NEWLINE > $LA
COUNT=`$TAIL -$LINE $LOGFILEPATH | egrep -c "$query"`
MATCHLINE=`$TAIL -$LINE $LOGFILEPATH | egrep -i "$query"`
        if [ "$COUNT" -ge "$critical" ];then
        $ECHO -e "CRITICAL Matches per line for $query is $COUNT, please refer the below error log.\n$MATCHLINE\nLast Line is $LASTLINE and New Line is $NEWLINE ";echo '|' "count=$COUNT;;$critical"
$PRINT "%b" "***** CRITICAL *****\n\nNotification Type: CRITICAL\n\nCRITICAL Matches per line for $query is $COUNT, please refer the below error log.\n\n$MATCHLINE\n\nDate&Time: $DATE" | $MAIL -s "** CRITICAL Alert: $query **" $CONTACTEMAIL
        exitstatus=$STATE_CRITICAL
        exit $exitstatus
        fi
fi
if [ "$NEWLINE" -eq "$LASTLINE" ] || [ "$COUNT" -lt "$critical" ];then
   $ECHO "OK - $COUNT pattern matches found,Last Line is $LASTLINE and New Line is $NEWLINE";echo '|' "count=$COUNT;;$critical"
   exitstatus=$STATE_OK
   exit $exitstatus
else
   $ECHO "UNKNOWN, Last Line is $LASTLINE and New Line is $NEWLINE";echo '|' "count=$COUNT;;$critical"
   exitstatus=$STATE_UNKNOWN
   exit $exitstatus
fi
fi
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e.g. ./check_log -F logfilepath(/var/log/messages) -q string(message) -c number of match

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It will through an error whenever there is a match.