md5 checksum

md5checksum.sh

#md5 generation
#  linux: md5sum file >md5file
#  mac:   md5 -r file >md5file

#Md5 comparison
#  linux: md5sum -c md5file
#  mac:   manual check ?

function find_md5sum() {
    OS=$(uname)
    # brew install md5sha1sum
    if [ "Darwin" == "$OS" ]; then
        echo "md5 -r"
    elif [ "Linux" == "$OS" ]; then
        echo "md5sum"
    else
        echo "Unsupported os: $OS"
        exit 1
    fi
}
md5sum=`find_md5sum`

#create md5 file
#${md5sum} update-modules-update.sh | awk {'print $1'} >digest.md5

NEWVAL=`${md5sum} update-modules-update.sh  | awk {'print $1'}`
OLDVAL=`cat ./digest.md5`

if [ "$NEWVAL" != "$OLDVAL" ] ; then
    echo "not equal"
    #do something...
else
    echo "equal"
    #do something...
fi