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gensio_close(3) 	    Library Functions Manual		 gensio_close(3)

NAME
     gensio_close,  gensio_close_s,  gensio_disable,  gensio_free  - Stop/free a
     gensio that is open

SYNOPSIS
     #include <gensio/gensio.h>

     typedef void (*gensio_done)(struct gensio *io, void *close_data);

     int gensio_close(struct gensio *io, gensio_done close_done,
			 void *close_data);

     int gensio_close_s(struct gensio *io);

     void gensio_disable(struct gensio *io);

     void gensio_free(struct gensio *io);

     gensio_close closes an open gensio.  Note that the close operation  is  not
     complete  until  close_done() is called.  This shuts down internal file de-
     scriptors and such, but does not free the gensio.	If the gensio is a  con-
     necting  one,  you can generally re-open it.  If you gensio_close before an
     open done is reported, the results (primarily  whether  the  open	done  is
     called)  are  undefined.  If the open done is called, it will be called be-
     fore the close done.

     gensio_close_s is like gensio_close, but blocks until the operation is com-
     plete.  BE VERY CAREFUL WITH THIS FUNCTION.  Do not call it from a callback
     because it waits until all operations on the  gensio  are	done,  and  they
     won't  be	done  until  the  callback returns.  You will deadlock if you do
     this.

     gensio_disable disables operation of the gensio so that  closing  will  not
     result  in  any data being transmitted.  THIS IS FOR EXTREMELY LIMITED USE.
     This will not close file descriptors nor disable I/O, necessarily, but will
     put the gensio stack into a state where freeing  will  not  result  in  any
     transmission  of  data  to  the other end.  You MUST be in a state where no
     callbacks are running or can run.	This is primarily to allow  a  close  of
     something	like  an  SSL connection after a fork.	If you didn't have this,
     the normal close in the one fork would shut down the SSL connection for the
     other fork, too.  See gensio(5) for details on forking.

     gensio_free frees data associated with the gensio.  If it is open, the gen-
     sio is closed.  If you  call  gensio_free	after  gensio_close  before  the
     close_done callback is called, whether close_done is called is undefined.

RETURN VALUES
     Zero is returned on success, or a gensio error on failure.

SEE ALSO
     gensio_err(3), gensio(5)

				   27 Feb 2019			 gensio_close(3)
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