PCH support on Solaris

Eric Botcazou ebotcazou@libertysurf.fr
Sun Apr 6 06:58:00 GMT 2003

> Do you mean that this code under Solaris
> size = 1048576
> guess = mmap (NULL, size, PROT_NONE,
> munmap (guess, size);
> addr = mmap (guess+4096, size-4096, PROT_NONE,
> printf ("%x %x\n", guess, addr);
> gives the same address for both guess and size?  That is, that Solaris
> completely ignores the first argument unless MAP_FIXED is given?

It appears so, indeed.

> If so, my idea is useless at least under Solaris.  But if not, I don't see
> your point.

No, it is not useless under Solaris, since

guess = mmap (NULL, size, PROT_NONE, MAP_PRIVATE, fd, 0);
munmap (guess, size);
addr = mmap (guess, size-4096, PROT_READ, MAP_PRIVATE, fd, 4096);
printf ("%x %x\n", guess, addr);

doesn't return the same address.

Eric Botcazou

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