...
Notes
See also GN_Esp which just displays the error message to standard output. Calling GN_Err with an invalid or fatal error message will cause a box with the error message and "Press Q to Quit - fatal error" to be displayed, and subsequently will generate a RC_QUIT system error. If you have an error handler in place, which handles RC_QUIT, then that code will be called.
The system call stacks the screen underneath the error window. RC_QUIT is returned if the user wants to quit. RC_DRAW is returned if the user wants to resume and screen needs re-drawing. RC_SUSP is returned the user wants to resume and the screen is preserved.
Related calls
GN_Esp, return an extended pointer to a system error message
OS_Erc, get error context
OS_Erh, set error handler
OS_Esc, examine special condition