io_wantread - signal that you want to read from a descriptor

       io_wantread  tells the next io_wait() that you want to read from this descriptor.  Call io_dontwantread()
       again if you change your mind.

       The next time you call io_wait(), it will look whether this descriptor becomes readable,  too.   You  can
       then use io_canread() to check whether the descriptor has become readable.

       You  have  to  have  called  io_fd  on  the descriptor first (io_pipe and io_socketpair do this 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.

       io_wantread - signal that you want to read from a descriptor

io_wait(3), io_canread(3), io_wantread(3), io_fd(3)

                                                                                                  io_wantread(3)

#include<libowfat/io.h>

       void io_wantread(int64 fd);