[
Example 1: 
Consider a function in this Clause that is specified to throw exceptions of type
system_error and specifies error conditions that include
operation_not_permitted for a thread that does not have the privilege to
perform the operation
.  Assume that, during the execution of this function, an 
errno
of 
EPERM is reported by a POSIX API call used by the implementation
.  Since POSIX
specifies an 
errno of 
EPERM when “the caller does not have the privilege
to perform the operation”, the implementation maps 
EPERM to an
error_condition of 
operation_not_permitted (
[syserr]) and an exception
of type 
system_error is thrown
. — 
end example]