Log monitor with email

logmond.sh

#!/bin/bash
# Monitor file for changes and send email notification
# Usage: ./logmond.sh /path/to/file recipient@domain.com

usage() {
    echo "Usage: ./logmond.sh /path/to/file recipient@domain.com"
}

if [ "$#" -ne 2 ]; then
    usage
    exit 1
fi

echo "Monitoring file ($1) for changes, email will be sent to ($2)"

cur_line_count="$(wc -l < $1)"
while true
do
    new_line_count="$(wc -l < $1)"
    if [ "$cur_line_count" != "$new_line_count" ]
    then
        lines_changed=$((new_line_count - cur_line_count))
        changes="$(tail -n $lines_changed $1)"
        echo "$changes" | s-nail -s "logmond Alert for $1" $2
    fi
    cur_line_count="$new_line_count"
    sleep 10
done