MD5SUM – Checksum on Linux

Use the following command to get a checksum

md5sum html/path/file.php

Create a file of checksums for future verification, here's just one file create a batch job to create lots of files instead.

md5sum html/path/file.php > md5sum_input.txt

Now check the md5 keys again, using md5sum_input.txt

md5sum -c md5sum_input.txt