by H.G.Muller » 12 May 2012, 22:25
The problem is that in WinBoard stderr (or stdout, etc.) is not open.
In XBoard stdin / stdout / stderr remain open, and associated with the terminal window from which you launched XBoard. This terminal is then also used as ICS interaction window. I think XBoard prints the result in the terminal because DisplayFatalError is used to display the result in a popup window. (Older versions used to always exit after finishing a match.) But DisplayFatalError also prints to the standard output, because some fatal errors can occur before the X-Windows stuff is initialized (e.g. during parsing of the command-line options), and at this time popups do not work yet. So then the terminal is the only place where the user can see the error message. (In WinBoard popups work from the very start, probably because it is compiled as a GUI application.)