NAME

       str_to_gensio,  str_to_gensio_child,  gensio_acc_str_to_gensio  -  Create  a gensio from a
       string

SYNOPSIS

       #include <gensio/gensio.h>

       int str_to_gensio(const char *str,
                           struct gensio_os_funcs *o,
                           gensio_event cb, void *user_data,
                           struct gensio **io);

       int str_to_gensio_child(struct gensio *child, const char *str,
                           struct gensio_os_funcs *o,
                           gensio_event cb, void *user_data,
                           struct gensio **io);

       int gensio_acc_str_to_gensio(struct gensio_accepter *accepter,
                           const char *str, struct gensio_os_funcs *o,
                           gensio_event cb, void *user_data,
                           struct gensio **io);

       int gensio_terminal_alloc(const char *gensiotype,
                           const void *gdata,
                           const char * const args[],
                           struct gensio_os_funcs *o,
                           gensio_event cb, void *user_data,
                           struct gensio **new_gensio);

       int gensio_filter_alloc(const char *gensiotype,
                           struct gensio *child,
                           const char * const args[],
                           struct gensio_os_funcs *o,
                           gensio_event cb, void *user_data,
                           struct gensio **new_gensio);

DESCRIPTION

       str_to_gensio allocates a new gensio stack based upon the given string str.

       str_to_gensio_child allocates a partial gensio stack and stacks it on  top  of  the  given
       child.   Note  that  if the child is already open, you should use gesnio_open_nochild() to
       open just this gensio.  This can only be used to allocate filter gensios.

       gensio_acc_str_to_gensio  allocates  a  gensio  based  upon  the  given   accepter.    The
       availability  and  use  of this varies from gensio to gensio, but it can be used on UDP to
       create a gensio that uses the UDP ports that the accepter owns.  This will come  from  the
       first  address/port  that  the  accepter  is  on for TCP and UDP.  It will bind to all the
       address/ports for SCTP.  To use this, you must specify a string that exactly  matches  the
       layers    of    the    accepter.     So,    for    instance,    if    the    accepter   is
       "telnet,ssl(CA=x1,key=x2,cert=x3),sctp,3095",  then  the  string  must  be  in  the   form
       "telnet,ssl(CA=x2),sctp,otherserver,3820"  The  layers  are  exactly the same, but you can
       vary the options to the layers.

       To directly allocation gensios, you can use gensio_terminal_alloc and gensio_filter_alloc.
       A  terminal  gensio is one at the bottom of the stack.  The gdata parameter depends on the
       particular gensio.  For instance, for serialdev it is a string specifying the  device  and
       serial parameters.  For stdio it is an argv array.  See gensio.5 under "Direct Allocation"
       for the particular gensio for what gdata is.

       A filter gensio is one that has a child.  You can use these two functions  to  allocate  a
       gensio stack directly, not using a string format.

       The  cb and user_data parameters set a function that will be called when events come in on
       the gensio.  user_data is unused by the gensio stack itself, it is there for the user  and
       may  be anything the user wishes.  cb may be NULL before the gensio is opened, but must be
       set before it is opened.  In particular, the cb does not need to be set if  other  gensios
       will  be stacked on top of it in the future, as the gensios stacked on top will set the cb
       and user_data values.

       The new gensio is returned in io.  It will be in the closed state.

RETURN VALUES

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

SEE ALSO

       gensio_set_callback(3), gensio_err(3), gensio(5)

                                           22 Feb 2019                           str_to_gensio(3)