>> On Jul 27 19:44, Thomas Wolff wrote: >>> Am 27.07.2015 um 17:58 schrieb Houder: >>> >Hi Thomas, >>> > >>> >Moving load_dwm_funcs() did the trick ... >>> > >>> > >>> Thanks again for your analysis. >>> In Control Panel â Performance Information and Tools â Adjust visual >>> effects, >>> it is only the last of the flags, â Use visual styles on windows and >>> buttons, >>> that makes the difference; if deselected, mintty crashes if called from a >>> console or somehow doubly isolated by >>> (setsid mintty &). >>> >>> Apparently, LoadLibrary does not propagate to a forked thread; >> >> Forked process, I hope :) >> >> No, it doesn't. Loading a library is purly process lokal on Windows. >> Cygwin DLLs(*) have special startup code which allows to register them >> in the process and to re-load them in the child process at fork time. >> >> (*) Actually, any DLL using this special entry point would work. >> Native Windows DLLs just don't, usually :} > > Ha, Corinna, you are the expert here, of course :-) > > From MSDN I learned (LoadLibrary() ): > > "Module handles are not global or inheritable. A call to LoadLibrary by > one > process does not produce a handle that another process can use in calling > GetProcAddress (as an example). The other process must make its OWN call > to > LoadLibrary for the module before calling GetProcAddress" > > Well, ok, alright, that makes sense ... > > However, if pDwmIsCompositionEnabled() returns 1, which will be the case if > one > has selected 'Windows 7' i.s.o. 'Windows Basic' (Personalization), > > as an example ... > > it turned out to be possible to invoke load_dwm_funcs() (i.e. LoadLibrary() ) > before the fork to a child withOUT a crash of the child !!!!! > > After all, it is Windows ????? > > No doubt, it will have been documented somewhere (DWM) ...
As an follow-up: The "companion" to pDwmIsCompositionEnabled(), i.e. pDwmExtendFrameIntoClientArea() made the child crash -- in update_glass(), Thomas, when 'Windows Basic' had been selected. Both "function pointers" always showed the same addresses, but when 'Windows Basic' had been selected, they turned out to be a jump into 'void'. Henri -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
