panel - manage overlapping curses windows

       Warren Tucker <wht@n4hgf.mt-park.ga.us> originally wrote this  implementation,  primarily  to  assist  in
       porting u386mon to systems without a native panel library.

       Zeyd ben-Halim repackaged it for ncurses.

       Juergen Pfeifer and Thomas E. Dickey revised and improved the library.

       Panels  are ncurses(3NCURSES) windows with the added property of depth.  Panel functions allow the use of
       stacked windows and ensure that the proper portions of each window  and  the  cursesstdscr  window  are
       hidden  or  displayed  when  panels are added, moved, modified, or removed.  The set of currently visible
       panels is the stack of panels.  The stdscr window is beneath all panels, and is not  considered  part  of
       the stack.

       A  window  is  associated with each panel.  The panel routines enable you to create, move, hide, and show
       panels.  You can relocate a panel to any desired position in the stack.

       Panel routines are a functional layer added to curses,  make  only  high-level  curses  calls,  and  work
       anywhere curses does.

bottom_panelbottom_panel(pan) puts panel pan at the bottom of all panels.

   ceiling_panelceiling_panel(sp) acts like panel_below(NULL) for the given SCREENsp.

   del_paneldel_panel(pan)  removes  the  given panel pan from the stack and deallocates the PANEL structure (but not
       its associated window).

   ground_panelground_panel(sp) acts like panel_above(NULL) for the given SCREENsp.

   hide_panelhide_panel(pan) removes the given panel pan from the panel stack and thus hides it from view.  The  PANEL
       structure is not lost, merely removed from the stack.

   move_panelmove_panel(pan,starty,startx)  moves the given panel pan's window so that its upper-left corner is at
       starty, startx.  It does not change the position of the  panel  in  the  stack.   Be  sure  to  use  this
       function, not mvwin(3NCURSES), to move a panel window.

   new_panelnew_panel(win)  allocates  a  PANEL structure, associates it with win, places the panel on the top of the
       stack (causes it to be displayed above any other panel) and returns a pointer to the new panel.

   panel_abovepanel_above(pan) returns a pointer to the panel above pan.  If the panel argument  is  “(PANEL*)0”,  it
       returns a pointer to the bottom panel in the stack.

   panel_belowpanel_below(pan)  returns  a pointer to the panel just below pan.  If the panel argument is “(PANEL*)0”,
       it returns a pointer to the top panel in the stack.

   panel_hiddenpanel_hidden(pan) returns FALSE if the panel pan is in the panel stack, and TRUE if it is  not.   If  the
       panel is a null pointer, it returns ERR.

   panel_userptrpanel_userptr(pan) returns the user pointer for a given panel pan.

   panel_windowpanel_window(pan) returns a pointer to the window of the given panel pan.

   replace_panelreplace_panel(pan,window)  replaces  the current window of panel pan with window This is useful if, for
       example, you want to resize a panel.  In ncurses, you can call replace_panel to resize a  panel  using  a
       window resized with wresize(3NCURSES).  It does not change the position of the panel in the stack.

   set_panel_userptrset_panel_userptr(pan,ptr) sets the panel's user pointer.

   show_panelshow_panel(pan)  makes a hidden panel visible by placing it on top of the panels in the panel stack.  See
       “PORTABILITY” below.

   top_paneltop_panel(pan) puts the given visible panel pan on top of all panels in  the  stack.   See  “PORTABILITY”
       below.

   update_panelsupdate_panels()  refreshes  the  virtual screen to reflect the relations between the panels in the stack,
       but does not call doupdate(3NCURSES)  to  refresh  the  physical  screen.   Use  this  function  and  not
       wrefresh(3NCURSES) or wnoutrefresh(3NCURSES).

       update_panels  may  be  called  more  than  once  before a call to doupdate, but doupdate is the function
       responsible for updating the physical screen.

       A panel facility was documented in SVr4.2's CharacterUserInterfaceProgramming document.

       It is not part of X/Open Curses.

       A few implementations exist:

       •   Systems based on SVr4 source code, such as Solaris, provide this library.

       •   ncurses  (since version 0.6 in 1993) and PDCurses (since version 2.2 in 1995) provide a panel library
           whose common ancestor is a public domain implementation by Warren Tucker published  in  u386mon  2.20
           (1990).

           According  to  Tucker,  the  System V  panel  library  was  first  released in SVr3.2 (1988), and his
           implementation helped with a port to SVr3.1 (1987).

           Several  developers  have  improved  each  of  these;  they  are  no  longer  the  same  as  Tucker's
           implementation.

       •   NetBSD  8  (2018)  has  a  panel  library  begun  by  Valery  Ushakov  in 2015, based on the System V
           documentation.

       panel - manage overlapping curses windows

       The header file panel.h itself includes the header file curses.h.

       Reasonable care has been taken to ensure compatibility with  the  native  panel  facility  introduced  in
       System V;  inspection  of  the  SVr4  manual pages suggests the programming interface never changed.  The
       PANEL data structures are merely similar.  The programmer is cautioned not to directly use PANEL fields.

       The functions show_panel and top_panel are identical in this implementation, and work equally  well  with
       displayed  or  hidden panels.  In the System V implementation, show_panel is intended for making a hidden
       panel visible (at the top of the stack) and top_panel is intended for  making  an  already-visible  panel
       move to the top of the stack.  You are cautioned to use the correct function to ensure compatibility with
       System V panel libraries.

       Each routine that returns a pointer returns NULL if an error occurs.  Each routine that  returns  an  int
       value returns OK if it executes successfully and ERR if not.

       Except  as  noted,  the  pan  and  window  parameters  must  be non-null.  If either is null, an error is
       returned.

       The move_panel function uses mvwin(3NCURSES), and returns ERR if mvwin returns ERR.

ncurses(3NCURSES), curses_variables(3NCURSES)

ncurses 6.5                                        2024-12-28                                    panel(3NCURSES)

#include<panel.h>PANEL*new_panel(WINDOW*win);intbottom_panel(PANEL*pan);inttop_panel(PANEL*pan);intshow_panel(PANEL*pan);voidupdate_panels(void);inthide_panel(PANEL*pan);WINDOW*panel_window(constPANEL*pan);intreplace_panel(PANEL*pan,WINDOW*window);intmove_panel(PANEL*pan,intstarty,intstartx);intpanel_hidden(constPANEL*pan);PANEL*panel_above(constPANEL*pan);PANEL*panel_below(constPANEL*pan);intset_panel_userptr(PANEL*pan,constvoid*ptr);constvoid*panel_userptr(constPANEL*pan);intdel_panel(PANEL*pan);/*ncursesextensions*/PANEL*ground_panel(SCREEN*sp);PANEL*ceiling_panel(SCREEN*sp);