Support for RT_SIGNAL_LEASE and sendfile?

[Chris00]

"Protecting" write from a mmap'ed with RT_SIGNAL_LEASE would allow the write to terminate reporting the number of bytes written before a possible interruption by, say, another process truncating the file. Would that be useful in Unix_cstruct and/or Lwt_cstruct?

In the same vein, Lwt_cstruct.sendfile may be useful (for example to send a big file on the wire using Cohttp). A similar function seems to be available on Windows.

Your thoughts?

[avsm]

I think both of these functions would be useful, but the RT_SIGNAL_LEASE needs to be protected to be linux-only, and sendfile should ideally be implemented upstream in Lwt.