matherr in dinkum

Anybody knows if and how the matherr function of the Dinkum libraries work?
The GNU libs used

matherr(struct _exception *ex);

What is the parameter of the Dinkum matherr(?) function?
Can’t find it in the docs


matherr is gone. The library reference show it under Deprecated
content.Other then that the QNX documentation is singularly un helpful.

Dinkums documentation shows that ‘errno’ is used. Math functions can set
either EDOM or ERANGE depending on the error.

The only other major mathematical error is division by zero. gcc deals with
with by generating a SIGFPE.