Re: Variable length MODS

[Scott Klement <klemscot@xxxxxxxxxxxx>]

On Tue, 17 Apr 2001, James David Rich wrote:

> I believe that the structure definition given below is illegal in other
> languages, i.e. you can't have:
> 
> char array[];
> 

That's true...   but you CAN do something like this:

char *array;

array = malloc(15001);
for (i=0; i<=15000; i++) {
     array[i] = ' ';
}
free(array);

In other words... although you can't declare it with 'char array[]',
you can still accomplish the same thing by declaring it with 
'char *array'.

The only problem with this is that the compiler/runtime doesn't
check if the index of the array is valid.   Sooner or later someone
will come along and do "malloc(15000)" instead of "malloc(15001)" 
and cause it to write a blank into an un-allocated area of memory.
That would be bad.

Perhaps if RPG were to do it's checking based on how much memory is
allocated to the basing pointer, it would be able to achieve the
best of both worlds, I don't know...



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