🚀 go-pugleaf

In article <1993Jan6.084522.25921@emr1.emr.ca> jagrant@emr1.emr.ca writes:

>At the risk of appearing stupid again, I have another (perhaps
>obvious, but not right now at 3:30 AM) question...
> [ Lots of stuff deleted]
>
>So, can someone tell me the difference between the following 2
>statements:
>        extern STUFF *stufftable;
>        extern STUFF stufftable[];
>with respect to the code generated when I reference stufftable, i.e.:
>        stufftable[i].xxx=...
>and explain why it is so dangerous here, but it's perfectly ok
>to use a pointer or a [] in a function declaration.
>-- 
>John A. Grant                                           jagrant@emr1.emr.ca
>Airborne Geophysics
>Geological Survey of Canada, Ottawa
>

The difference is very simple:

    extern STUFF *stufftable

tells the complier that you have a global variable which is a POINTER to
a "stufftable".  ie, the global quantity is a 2 or 4-byte pointer.

    extern STUFF stufftable[]

tells the compiler that you have a global ARRAY of STUFFs.

The two things are totally different.  The reason that it doesn't matter
in a function declaration is that passing the name of an array to a function
is the same as passing a pointer to the start of the array.

Hope this helps,
-- 
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| Chris Marriott                           | chris@chrism.demon.co.uk    |
| Warrington, UK                           | BIX: cmarriott              |
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