On Thu, Sep 24, 2020 at 03:09:05PM +0200, Albretch Mueller wrote:
> rsync uses crc for its data integrity checks. Why is it you can't use
> it like any other OS utility?
>
> $ date; which crc
> Thu Sep 24 07:54:55 CEST 2020
>
CRC is a family of checksum algorithms. They're generally considered
to be primitive and outdated. For the most part, you won't find
standalone tools for each CRC variant. You could probably find one tool
that implements several of them, with options to select the one you
would like.
Tab completion tells me I've got one called "crc32" installed.
unicorn:~$ dpkg -S /usr/bin/crc32
libarchive-zip-perl: /usr/bin/crc32
>From its man page:
Note that the CRC-32 checksum is merely used for error detection in
transmission and storage. It is not intended to guard against the ma‐
licious modification of files (i.e., it is not a cryptographic hash).
There may very well be others. Or, you could implement the algorithm(s)
yourself in C. It would make a nice little freshman computer science
homework assignment.
