io_fd(3) [debian man page]

io_fd(3)						     Library Functions Manual							  io_fd(3)

NAME

       io_fd - prepare descriptor for io_wait

SYNTAX

       #include <io.h>

       int io_fd(int64 fd);

DESCRIPTION

       If  you	want to use io_canread() and io_canwrite() on a descriptor, you have to use io_wait() on it first, and io_wait() has to know which
       descriptors you are interested in.  Use io_fd() for this.

       io_pipe and io_socketpair already call io_fd for you.

       Waiting on descriptors only works for sockets, fifos and pipes.	It may also work on devices and TTYs, but that is  platform  dependent	--
       you should not rely on that.  It does not work on files.

RETURN VALUE

       io_fd returns 1 on success, 0 on error.

SEE ALSO

       io_wait(3), io_wantread(3), io_canread(3), io_eagain(3), io_nonblock(3)

																	  io_fd(3)

iob_write(3)						     Library Functions Manual						      iob_write(3)

NAME

       iob_write - send I/O batch through callback

SYNTAX

       #include <iob.h>

       typedef int64 (*io_write_callback)(int64 s,const void* buf,uint64 n);

       int64 iob_write(int64 s,io_batch* b,io_write_callback cb);

DESCRIPTION

       iob_write sends the (rest of) b through the callback cb, passing s as first argument.  cb is expected to behave like io_trywrite(2).

       This  interface	is intended to send an I/O batch through a filter, for example to encrypt or compress it.  If you just want to send an I/O
       batch to a socket, use iob_send instead.

       iob_write returns the number of bytes written, 0 if there were no more bytes to be written in the batch, -1 for EAGAIN, or -3 for a  perma-
       nent error (for example "connection reset by peer").

       The normal usage pattern is using io_wait to know when a descriptor is writable, and then calling iob_write until it returns 0, -1 or -3.

       If  it  returns	0,  terminate  the  loop (everything was written OK).  If it returns -1, call io_wait again.  If it returned -3, signal an
       error.

NOTE

       iob_write will continue to call your callback until it returns an error.  So if you are in a state machine, for example a web server  using
       this  for  SSL  support,  make  sure  to  write at most n bytes at a time (e.g. 64k) and the next time you are called return -1.  Otherwise
       iob_write might not return until the whole file is served.

SEE ALSO

       iob_send(3)

																      iob_write(3)