On Sat, Mar 07, 1998 at 04:12:22PM -0800, tooleym@douglas.bc.ca wrote:
> 
> >From a recent ./configure that I ran to install xfmail, I was told rather
> rudely (IMHO) that I needed a functional mmap() in order to run the
> program correctly.
> 
> Do we not have a working mmap()?
> 

The issue here is that the VM and buffer cache are not coherent, i.e.
any changes that you make through mmap() will not be reflected
in the buffer cache (i.e. you will not see them with read()/write()),
and vice versa.

UVM itself does not fix that, but it will be fixed at some point.

If some program really needs to see mmap() changes reflected
immediately, the normal way of doing this is through msync().

- Frank