pointer question: * space name

FILE *open

and

FILE * open

are same thing. Space between * open makes any different?

same thing, no difference.

FILE* open
FILE * open
FILE *open
All the same thing.

If you do this
int* ptr, var;
you might be tempted into thinking that var was a ptr to an int (it isn't).

int *ptr, var;
Would make it clearer that the 'pointer' belonged to the ptr variable only, and not to var.

On the other hand, it's worth noting that mixing declarations like this is poor style to begin with. The amount of effort it saves is much less than the confusion it can cause.

I like to think that int* a pointer to an int, but I also know that int* ptr, var, only ptr is int* and var is int, and thus I never declare more than one pointer per line.
Go, go, C/C++ semantics!