This is the mail archive of the
cygwin@cygwin.com
mailing list for the Cygwin project.
Re: assertion "ptr != MAP_FAILED" failed while using mmap
Alex Vinokur wrote:
> char* ptr = (char*)mmap(0, sz, PROT_READ, 0, fd, 0);
>
> errno = 0;
> if (ptr != MAP_FAILED)
> {
> string str(ptr, ptr+sz);
> munmap(ptr, sz);
> }
> else
> {
> assert (ptr == MAP_FAILED);
> printf ("=== Error : %u %s ===\n", errno, strerror (errno));
> }
> The program prints:
> === Error : 0 No error ===
Of course it does, since you set errno = 0, what else could you possibly
expect? Remove that line if you want to know why mmap() fails.
Brian
--
Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Problem reports: http://cygwin.com/problems.html
Documentation: http://cygwin.com/docs.html
FAQ: http://cygwin.com/faq/