mmapplypolicy -L 0

Use this option to display only serious errors.

In this example, there is an error in the policy file. This command:
mmapplypolicy fs1 -P policyfile -I test -L 0
produces output similar to this:
[E:-1] Error while loading policy rules.
PCSQLERR: Unexpected SQL identifier token - 'EXCULDE'.
PCSQLCTX: at line 8 of 8: RULE 'exclude 2' {{{EXCULDE}}}
mmapplypolicy: Command failed.  Examine previous error messages to determine cause.
The error in the policy file is corrected by removing these lines:
/* Typo in rule */ 
RULE 'exclude 2' EXCULDE
Now rerun the command:
mmapplypolicy fs1 -P policyfile -I test -L 0

No messages are produced because no serious errors were detected.