A wrapper around a Unix.file_descr.

of_unix ~sw ~close_unix fd wraps fd.

• parameter sw

  Close fd automatically when sw is finished.

• parameter blocking

  Indicates whether fd is in blocking mode. If not given, fd is probed for its blocking state if needed.

• parameter seekable

  The value to be returned by is_seekable. Defaults to probing if needed.

• parameter close_unix

  Whether close also closes fd (this should normally be true).

use t fn ~if_closed calls fn wrapped_fd, ensuring that wrapped_fd will not be closed before fn returns.

If t is already closed, it returns if_closed () instead.

use_exn op t fn calls fn wrapped_fd, ensuring that wrapped_fd will not be closed before fn returns.

If t is already closed, it raises an exception, using op as the name of the failing operation.

use_exn_list op fds fn calls use_exn on each FD in fds, calling fn wrapped_fds on the results.

close t marks t as closed, so that use can no longer be used to start new operations.

The wrapped FD will be closed once all current users of the FD have finished (unless close_unix = false).

Has no effect if t is already closed.

remove t marks t as closed, so that use can no longer be used to start new operations.

It then waits for all current users of the wrapped FD to finish using it, and then returns the FD.

This operation suspends the calling fiber and so must run from an Eio fiber. It does not allow itself to be cancelled, since it takes ownership of the FD and that would be leaked if it aborted.

Returns None if t is closed by another fiber first.

is_blocking t returns the value of blocking passed to of_unix.

If not known, it first probes for it (and if the FD is already closed, returns false).

is_seekable t returns the value of seekable passed to of_unix.

If not known, it first probes for it (and if the FD is already closed, returns false).

Displays the FD number.