Check correctness of pathname

testpath.sh

#!/bin/bash

DELIM="/"
FILE="[a-zA-Z]([a-zA-Z0-9])*"
R="(${DELIM})?${FILE}(${DELIM}${FILE})*${DELIM}?"

path=$1

echo "$path" | egrep -x "$R"

[ $? -eq 0 ] && {
    echo "OK"
    exit 0
}

echo "NOK"
exit 1