We have really devolved. In VMS (later OpenVMS, which change didn’t help much) messages have the following format:
-RMS-E-FNF, file not found
-SYSTEM-W-NOSUCHFILE, no such file
Facility is an OS component, in this case the file system.
s is severity, in this case Warning.
identification is the message id.
You can capture (trap) the $STATUS in your script as a unique hex number and process it accordingly without failing the script. You can also get further help on the message.
All this was possible in the early 1980s.
WRTHOMBLK, I/O error rewriting home block