[erlang-questions] Information on file:advise/4

[Valentin Micic]

Hi, 

Would it be possible for someone to shed a bit more light on various posix_file_advise() options in file:advise/4 function?

For example, I could guess that 'will_need' may ask OS to buffer the file, whilst 'don't_need' may have an opposite effect.
I could also guess that 'sequential' should instruct OS to provide for a larger working I/O buffer than in a case of 'random'.

But what about 'no_resue' or 'normal'?

Finally, it would be good to know when one should reference these functions? Immediately after opening the file, or when required.

Thanks in advance.

V/