/****************************************************************
 * File: vns_comm.c
 * Date: 03/07/91
 *
 * Description:
 *   This file contains several client functions that communicate
 *   with VNS. These functions allows client applications to "tell"
 *   VNS to do things such as display a page.
 *
 * Revisions:
 ****************************************************************/
/****************************************************************
 *              Private Functions
 ****************************************************************/
/****************************************************************
 *              Client Functions
 ****************************************************************/
/****************************************************************
 * Function: vns_open_xdisplay() 
 * Date: 03/11/91
 *
 * Description:
 *   This function establishes a display connection with the X
 *   server. This function is provided so that non-X applications
 *   can use the vns_comm library.
 *
 * Linkage: Display *vns_open_xdisplay()
 *
 * Returns: The X display pointer if successful. NULL otherwise.
 *
 * Revisions:
 ****************************************************************/
/****************************************************************
 * Function: vns_initialize 
 * Date: 03/11/91
 *
 * Description:
 *   This function initializes the vns_comm library. If successful,
 *   it returns the connection pointer.
 *
 * Linkage: VnsConnection *vns_initialize(dpy,db)
 *   Display *dpy - The X diplay connection pointer
 *   char *db     - database name
 *
 * Returns: the vns connection pointer if successful. NULL otherwise.
 *
 * Revisions:
 ****************************************************************/
/****************************************************************
 * Function: vns_display_page
 * Date: 03/11/91
 *
 * Description:
 *   This function opens a specific page in the specified notebook.
 *
 * Linkage: int vns_display_page(vc,nid,pid)
 *   VnsConnection *vc - connection pointer (see vns_initialize)
 *   int nid           - notebook id
 *   int pid           - page id
 *
 * Revisions:
 ****************************************************************/
/****************************************************************
 * Function: vns_select_page
 * Date: 04/09/91
 *
 * Description:
 *   This function asks VNS to allow the user to select a page
 *   and return the full path to this page. VNS will activate
 *   the "link-here" icons for all displayed pages allowing
 *   the user to select a page.
 *
 * Linkage: char *vns_select_page(vc)
 *   VnsConnection *vc - connection pointer (see vns_initialize)
 *
 * Revisions:
 ****************************************************************/
/****************************************************************
 * Function: vns_close_page
 * Date: 04/09/91
 *
 * Description:
 *   This function tells VNS to close the specified page.
 *
 * Linkage: int vns_close_page(vc,nid,pid)
 *   VnsConnection *vc - connection pointer (see vns_initialize)
 *   int nid           - notebook id
 *   int pid           - page id
 *
 * Revisions:
 ****************************************************************/
/****************************************************************
 * Function: vns_show_outlines
 * Date: 03/12/91
 *
 * Description:
 *   This function tells VNS to show outlines around objects.
 *
 * Linkage: int vns_show_outlines(vc,state)
 *   VnsConnection *vc - connection pointer (see vns_initialize)
 *   Boolean state     - on or off state
 *
 * Revisions:
 ****************************************************************/
/****************************************************************
 * Function: vns_exit
 * Date: 03/12/91
 *
 * Description:
 *   This function free the connection pointer and cleans up
 *   after the clinet.
 *
 * Linkage: int vns_exit(vc)
 *   VnsConnection *vc - connection pointer (see vns_initialize)
 *
 * Revisions:
 ****************************************************************/