> From: Felix Oxley <lkml@xxxxxxxxx>
>
> In certain places I have seen the following code:
> (e.g. scripts/pnmtologo.c or arch/ppc/platforms/chrp_setup.c)
>
> static const char *foo = "ABC";
>
> int main(int argc, char *argv[])
> {
> foo = "some other value";
> }
>
>
> How can this be allowed? foo has been declared constant and yet is being
> assigned a new value ?
The "const char *" means it's a pointer to constant characters. The characters are constant, but not the pointer. The assignment, foo = "...", changes the pointer, but not the characters, so it's valid.
> Also, I have seen a lot of: const char *foo = "";
> There would be no point in declaring a constant empty string so it must be
> given a new value elsewhere in the code.
Again, the characters are empty, but not the pointer, so the pointer may be assigned to a different character string.
HTH
Mark
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