           panel - panel stack extension for curses

## SYNOPSIS

           #include <panel.h>

           cc [flags] sourcefiles -lpanel -lncurses

           PANEL *new_panel(WINDOW *win)
           int bottom_panel(PANEL *pan)
           int top_panel(PANEL *pan)
           int show_panel(PANEL *pan)
           void update_panels();
           int hide_panel(PANEL *pan)
           WINDOW *panel_window(const PANEL *pan)
           int replace_panel(PANEL *pan, WINDOW *window)
           int move_panel(PANEL *pan, int starty, int startx)
           int panel_hidden(const PANEL *pan)
           PANEL *panel_above(const PANEL *pan)
           PANEL *panel_below(const PANEL *pan)
           int set_panel_userptr(PANEL *pan, const void *ptr)
           const void *panel_userptr(const PANEL *pan)
           int del_panel(PANEL *pan)

## DESCRIPTION

           Panels  are  curses(3X)  windows with the added feature of
           depth.  Panel functions allow the use of  stacked  windows
           and  ensure  the  proper  portions  of each window and the
           curses stdscr window are hidden or displayed  when  panels
           are  added,  moved,  modified or removed.  The set of cur-
           rently 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 every panel.  The  panel  rou-
           tines  enable you to create, move, hides, and show panels,
           as well as position a panel at any desired location in the
           stack.

           Panel routines are a functional layer added to curses(3X),
           make only high-level curses calls, and work anywhere  ter-
           minfo curses does.

## FUNCTIONS

           new_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.

           void update_panels()
                  refreshes the virtual screen to reflect  the  rela-
                  tions between the panels in the stack, but does not
                  update_panels() may be called more than once before
                  a  call  to doupdate(), but doupdate() is the func-
                  tion responsible for updating the physical  screen.

           del_panel(pan)
                  removes the given panel from the  stack and deallo-
                  cates the PANEL structure (but not  its  associated
                  window).

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

           show_panel(pan)
                  makes  a  hidden panel visible by placing it on top
                  of the panels in the panel stack. See COMPATIBILITY
                  below.

           top_panel(pan)
                  puts  the  given visible panel on top of all panels
                  in the stack.  See COMPATIBILITY below.

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

           move_panel(pan,starty,startx)
                  moves the given panel 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(), to move a panel
                  window.

           replace_panel(pan,window)
                  replaces the current window of  panel  with  window
                  (useful, for example if you want to resize a panel;
                  if you're using ncurses, you can call replace_panel
                  on  the output of wresize(3x)).  It does not change
                  the position of the panel in the stack.

           panel_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_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.

           set_panel_userptr(pan,ptr)
                  sets the panel's user pointer.
                  returns the user pointer for a given panel.

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

## DIAGNOSTICS

           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.

## COMPATIBILITY

           Reasonable  care  has been taken to  ensure  compatibility
           with  the  native  panel  facility  introduced  in  SVr3.2
           (inspection of the SVr4 manual pages suggests the program-
           ming interface is unchanged).  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 dis-
           played or hidden panels.  In the native System V implemen-
           tation, 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  native  panel
           libraries.

## NOTE

           In your library list, libpanel.a should  be  before  libn-
           curses.a;  that  is,  you want to say `-lpanel -lncurses',
           not the other way around (which  would  give  you  a  link
           error using GNU ld(1) and some other linkers).

## FILES

           panel.h interface for the panels library

           libpanel.a the panels library itself

## SEE ALSO

           curses(3X)

## AUTHOR

           Originally   written   by   Warren  Tucker  <wht@n4hgf.mt-
           park.ga.us>, primarily to assist  in  porting  u386mon  to
           systems  without  a native panels library.  Repackaged for
           ncurses by Zeyd ben-Halim.