To report a fatal error, and write the relevant description of it in the trace file (see
how_vely_works) regardless of whether tracing is enabled or not, use report-error. The error message is output in the same fashion as in
pf-out, where <format> (of string type) and <expression>s (of any type) are used as in C's
"printf()" function.
Note that you must always have at least one <expression>, even when the entire output is just a string constant, so for example you would write:
report-error "%s", "Bad value for number of processes"
The reason for this is to avoid formatting errors, and to use formatting in a consistent fashion.
See
error_handling when report-error is called.
