Shell Programming and Scripting

MMRR0106.DAT
MMRR0206.DAT
MMRR0406.DAT
MMRR0506.DAT
MMRR0806.DAT
....
...
MMRR3006.DAT
MMRR0207.DAT

MMRR0306.DAT
MMRR0606.DAT
MMRR0706.DAT
MMRR0107.DAT

#!/bin/sh
start_number=1
current_number=0
errfound=0
errfiles=""


for file in $(ls /venky); do
    current_number="${start_number}"
    file_error=0
    while read line; do 
        if [ ! "${line}" = "${current_number}" ]; then
            echo "Missing number: ${current_number}"
            file_error=1
        fi  
    done < $file
    if [ "${file_error}" -ne 0 ]; then
        errfiles="${errfiles}${file} "
    fi
done
if [ ! -z "${errfiles}" ]; then
    echo "The following files are missing numbers:"
    echo "${errfiles}"
fi
exit 0

awk 'p && p != $1 { for( i = p; i < $1; i++ ) print i; } {p = $1 + 1 }' input-file