Using global struct

[David812]

Dear All,
I've a problem using a global struct.
Is possible to use it in Qt?
I've tried to declare it in a global.h file a struct
such as :

extern struct _Stxy1000{
	 double dY[];
	 double dX[];
}

extern struct _Stxy1000{
	 double dY[];
	 double dX[];
}

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then i've put in a global.cpp file

struct _Stxy1000{
	 double dY[1000];
	 double dX[1000];
}_stxy1000;

struct _Stxy1000{
	 double dY[1000];
	 double dX[1000];
}_stxy1000;

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when i try i acces to the struct member the compiler rise up some errors such as, the struct is not declared, even if i include the global.h in a proper way.
Thanks in advance