nagios监控apache进程数

nagios监控apache的进程数的脚本，同时学习到了一个新的命令：getopts，现把脚本分享如下。
#!/bin/bash
. /usr/local/nagios/libexec/utils.sh
#AUTHOR by wenzizone.cn
VERSION="1.0"
CHECKNAME="HTTP process"
PS=/bin/ps
GREP=/bin/grep
WC=/usr/bin/wc
FLAG_VERBOSE=FALSE
LEVEL_WARN=""
LEVEL_CRIT=""
RESULT=""
EXIT_STATUS=$STATE_OK
usage() {
    echo " check_apacheprocess $VERSION - Nagios Apache concurrent HTTP process number check script"
    echo ""
    echo " Usage: check_apacheprocess -w <warning level> -c <critical level> [ -h ]"
    echo ""
    echo "         -w  Number of concurrent process number at which a warning is triggered"
    echo "         -c  Number of concurrent process number at which a critical is triggered"
    echo "         -h  Show this page"
    echo ""
}
doopts() {
    if ( test 0 -lt $# )
    then
        while getopts w:c:vh myarg
        do
            case $myarg in
                h|?)
                    usage
                    exit;;
                w)
                    LEVEL_WARN=$OPTARG;;
                c)
                    LEVEL_CRIT=$OPTARG;;
                *)    # Default
                    usage
                    exit;;
            esac
        done
    else
        usage
        exit
    fi
}
theend() {
    echo $RESULT
    exit $EXIT_STATUS
}
doopts $@
OUTPUT=$($PS fax|$GREP httpd|$GREP -v grep|$WC -l)
if test -z "$OUTPUT" ; then
    RESULT="$CHECKNAME WARNING - query returned no output!"
    EXIT_STATUS=$STATE_WARNING
else
    if test "$OUTPUT" -lt "$LEVEL_WARN" ; then
        RESULT="$CHECKNAME OK - $OUTPUT concurrent process"
        EXIT_STATUS=$STATE_OK
    else
        if test "$OUTPUT" -gt "$LEVEL_CRIT" ; then
            RESULT="$CHECKNAME CRITICAL - $OUTPUT concurrent process"
            EXIT_STATUS=$STATE_CRITICAL
        else
            if test "$OUTPUT" -gt "$LEVEL_WARN" ; then
                RESULT="$CHECKNAME WARNING - $OUTPUT concurrent process"
                EXIT_STATUS=$STATE_WARNING
            fi
        fi
    fi
fi
# Quit and return information and exit status
theend