How to do a checksum checksum of files on a schedule in Linux?

Question

css

You need to check the integrity of the contents of all files in the specified directories on a schedule. Something similar to an old antivirus, when checksums were collected during the 1st pass, and then they were simply checked in order to find changed files.
Before writing a bicycle, I would like to know if there is a ready-made solution?

Answer 1

codepen.io/DNLHC/pen/yOozRZ you
can do the same with a border

Answer 2

pseudo-class can also appear on hover

.classname:after {
opacity:0;
}

.classname:hover:after {
opacity:1;
}

Answer 3

In the most trivial case, it suffices
to create a list of checksums and
to verify it. Any other *sum can be used instead of md5sum.
Of the more civilized, there is Tripwire .

Answer 4

There is inotify, with it you can track file changes.