debian man page for iob_send

iob_send(3)						     Library Functions Manual						       iob_send(3)

NAME
       iob_send - send I/O batch

SYNTAX
       #include <iob.h>

       int64 iob_send(int64 s,io_batch* b);

DESCRIPTION
       iob_send sends the (rest of) b over the socket s.

       iob_send  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_send 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
       and close the socket.

       The benefit of the I/O batch API is that it exploits platform specific APIs like FreeBSD's sendfile.  The file contents will always be sent
       in a way that allows the operating systems to perform zero copy TCP, and the buffers will always be sent using as few syscalls as  possible
       and avoiding unnecessary copying (using writev).

SEE ALSO
       iob_reset(3), iob_send(3), iob_addbuf(3), iob_adds_free(3), iob_addfile(3), iob_prefetch(3)

																       iob_send(3)