Function: errname
Section: programming/specific
C-Name: errname
Prototype: G
Help: errname(E): returns the type of the error message E.
Doc: returns the type of the error message \kbd{E} as a string.
 \bprog
 ? iferr(1 / 0, E, print(errname(E)))
 e_INV
 ? ?? e_INV
 [...]
 * "e_INV".  Tried to invert a noninvertible object x in function s.
 [...]
 @eprog
Description:
 (gen):errtyp err_get_num($1)
