[Ipopt] print_level and output_file options

[Brad Bell]

I have a multi-level optimization problem. Each time I evaluate the 
object for the output problem, the inner problem must be solved. 
Sometimes (for very simple test cases) I wish to trace both the inner 
and output problems in separate files.  The Ipopt documentation contains 
the following text:

output file:
File name of desired output file (leave unset for no file output). NOTE: 
This option only works when read from the ipopt.opt options file! ...

Is it possible to set a different output file for this inner and outer 
problem without using the options file; i.e., using the C++ interface 
for setting options ?