> You'll need to register a custom error handler. Actually, on a second read through the documentation, gsl_set_error_handler_off() should do what you want. Surround your call with something like the following:
gsl_set_error_handler_off(); result = gsl_root_fdfsolver_newton(...); gsl_set_error_handler(NULL); and then check result against the standard GSL error codes. - Rhys
