Although the Message Reporting System could be used for reporting errors, there are a number of considerations which demand that separate facilities are available for this:
This can lead to several error reports arising from a single failure.
These considerations have led to the design and implementation of a set of subroutines which form the Error Reporting System. The subroutines have names of the form:
ERR_name
where name indicates what the subroutine does. These subroutines work in conjunction with the Message System and allow error messages to incorporate message tokens.
MERS (MSG and ERR) Message and Error Reporting Systems