LIBHANDOFF0(3)						      Copyright FSF 1996-2006						    LIBHANDOFF0(3)

NAME

       libhandoff - handoff library for GPE calendar.

SYNOPSIS

       extern GType handoff_get_type(void);

       typedef void (*HandoffCallback)(Handoff *handoff, char * data);

       extern Handoff * handoff_new(void);

       extern gboolean handoff_handoff(Handoff *handoff, const char *rendezvous, const char *data, gboolean display_relevant,
				       char *(*serialize) (Handoff *), void (*exit)(Handoff *));

DESCRIPTION

       This manual page briefly describes the libhandoff0 API.

       This manual page was written for the Debian distribution because the original program does not have a manual page.

       libhandoff is used in the GPE Palmtop Environment to cause another program instance to come to the foreground. This is used when alarm
       triggers (like atd) wake the device and then need to load another program to show the reason for the device waking up. When gpe-calendar
       starts it looks at a well known location to find another instance of itself. If it does, it tells that instance to grab the focus.

       This man page is for libhandoff0 version 0.1.

FUNCTIONS

       The Handoff and HandoffClass structs are opaque. Use handoff_new to return a new Handoff * instance.

       typedef void (*HandoffCallback)(Handoff *handoff, char * data);

       The "handoff" signal is triggered when another instance successfully negotiates a handoff to this instance. DATA is the data sent by other
       instance, normally a serialization of state this instance should use.

       extern Handoff * handoff_new(void);

       Create a new passive handoff. Before calling handoff_handoff, the caller should connect a handler to the "handoff" signal.

       extern gboolean handoff_handoff(Handoff *handoff, const char *rendezvous, const char *data, gboolean display_relevant,
				       char *(*serialize) (Handoff *), void (*exit)(Handoff *));

       Try to handoff this instance to an already running process.

       rendezvous is the address which all instances of this program rendezvous with.

       If another instance of the program is contacted then: if display_relevant is true, the value of the environment variable DISPLAY is sent;
       and if data is non-NULL, its value is sent. If the handoff request (DISPLAY is either not sent or they are identical), this function
       returns TRUE and this instance should proceed to exit. Otherwise, if the other instance punts, it sends a serialization of its state and
       the "handoff" signal is fired and TRUE is returned.

       If no running instance is found to be listening on rendezvous or the instance punts, this instance attempts to bind to rendezvous so that
       subsequent instances can find this instance and FALSE is returned.

       After connecting, this instance waits on rendezvous for other instances to connect. When an instance connects and hands off its state, the
       "handoff" signal is fired. If this instance decides to yield (based on the above criteria), then serialize is called to serialize any
       state. Once the handoff completes, exit is called and this instance should proceed to do any final clean up and exit.

AUTHOR

       This manual page was written by Neil Williams <linux@codehelp.co.uk> for the Debian system (but may be used by others). Permission is
       granted to copy, distribute and/or modify this document under the terms of the GNU General Public License, Version 2 any later version
       published by the Free Software Foundation.

       On Debian systems, the complete text of the GNU General Public License can be found in /usr/share/common-licenses/GPL.

libhandoff 3						   Wed 25 Apr 2007 10:58:46 BST 					    LIBHANDOFF0(3)