c - Passing struct as a parameter in place of void* -

i have function accepts void* parameter, want use if it's struct.

typedef struct struct1 {     int val; } struct2;  void func1(void* struct3) {     printf("%d",struct3->val); }

my purpose example, if have .h file function defined as

typedef void* parameter1; void func1(parameter1 p1);

and wants use struct parameter in function, without declaring struct in .h file.

thanks answer printf("%d",((struct2 *)struct3)->val) mentioned @i486, that's looking for.

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