panel(3CURSES)

✨ NAME ✨

okay so bestie, welcome to panel — it's the panel stack extension for curses 💅 this is from the panel(3CURSES) manual page and it's literally about stacking windows on top of each other like the most organized girlie in the group chat.

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🌸 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(void);
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);

/* ncurses-extensions */
PANEL *ground_panel(SCREEN *sp);
PANEL *ceiling_panel(SCREEN *sp);

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🦋 DESCRIPTION 🦋

Panels are ncurses(3NCURSES) windows but with the extra girlboss feature of depth. The panel functions let you use stacked windows, and they make sure the right portions of each window — and of the curses stdscr window — get hidden or displayed whenever panels are added, moved, modified or removed. The set of currently visible panels is the stack of panels. And stdscr? She sits beneath all panels and is not considered part of the stack. Sorry babe.

Every panel has a window associated with it. The panel routines let you create, move, hide and show panels, and also put a panel at literally any position in the stack you want. Main character placement, honestly.

Panel routines are a functional layer added onto ncurses(3NCURSES), they only make high-level curses calls, and they work anywhere terminfo curses works. 🌈

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💖 FUNCTIONS 💖

bottom_panel

bottom_panel(pan) puts panel pan at the bottom of all panels. humble era, but make it intentional.

ceiling_panel

ceiling_panel(sp) acts like panel_below(NULL), for the given SCREEN sp.

del_panel

del_panel(pan) removes the given panel pan from the stack and deallocates the PANEL structure — but not its associated window. the window lives on, she's fine.

ground_panel

ground_panel(sp) acts like panel_above(NULL), for the given SCREEN sp.

hide_panel

hide_panel(pan) removes the given panel pan from the panel stack, which means it gets hidden from view. The PANEL structure isn't lost though — it's just taken off the stack. ghosting the stack, not deleting the panel.

move_panel

move_panel(pan,starty,startx) moves the given panel pan's window so its upper-left corner is at starty, startx. It does not change where the panel sits in the stack.

okay listen: use this function, not mvwin(3X), when you're moving a panel window. fr fr.

new_panel

new_panel(win) allocates a PANEL structure, associates it with win, places the panel on top of the stack (so it gets displayed above any other panel) and returns a pointer to the new panel. new panel, new me. ✨

panel_above

panel_above(pan) returns a pointer to the panel above pan. And if the panel argument is (PANEL *)0, it returns a pointer to the bottom panel in the stack.

panel_below

panel_below(pan) returns a pointer to the panel just below pan. And if the panel argument is (PANEL *)0, it returns a pointer to the top panel in the stack.

panel_hidden

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

panel_userptr

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

panel_window

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

replace_panel

replace_panel(pan,window) replaces the current window of panel pan with window. Super useful — like, say, if you want to resize a panel. In ncurses you can call replace_panel to resize a panel using a window that's been resized with wresize(3NCURSES). It does not change the position of the panel in the stack.

set_panel_userptr

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

show_panel

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

top_panel

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

update_panels

update_panels() refreshes the virtual screen to reflect the relations between the panels in the stack — but it does not call doupdate(3X) to refresh the physical screen.

use this function, and not wrefresh(3X) or wnoutrefresh(3X). i'm serious.

update_panels can be called more than once before a call to doupdate, but doupdate is the function that's actually responsible for updating the physical screen.

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💀 DIAGNOSTICS 💀

Every routine that returns a pointer returns NULL if an error occurs. Every routine that returns an int value returns OK if it executes successfully, and ERR if it doesn't.

Except where noted, the pan and window parameters must be non-null. If those are null, an error is returned. no nulls allowed, babe.

The move_panel function uses mvwin(3X), and will return an error if mvwin returns an error.

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🫶 COMPATIBILITY 🫶

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 is unchanged). The PANEL data structures are merely similar though. So the programmer is cautioned not to directly use PANEL fields. do not touch the internals. hands off.

The functions show_panel and top_panel are identical in this implementation, and they work equally well with displayed or hidden panels. But in the native 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 native panel libraries. pick wisely bestie.

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⭐ NOTE ⭐

In your library list, libpanel.a should come before libncurses.a. So like, you should say -lpanel -lncurses, and not the other way around — because the other way around gives you a link-error with static libraries. order matters, always. 💅

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🌈 PORTABILITY 🌈

The panel facility was documented in SVr4.2 in Character User Interface Programming (UNIX SVR4.2).

It is not part of X/Open Curses.

A few implementations exist:

• Systems based on SVr4 source code, e.g., 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 was a public domain implementation by Warren Tucker published in u386mon 2.20 (1990).
  • According to Tucker, the SystemV 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. This is based on the AT&T documentation.

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🎀 FILES 🎀

• panel.h — interface for the panels library
• libpanel.a — the panels library itself

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👑 SEE ALSO 👑

ncurses(3NCURSES), curses_variables(3NCURSES),

This describes ncurses version 6.4 (patch 20221231).

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🧚 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.

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

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and that's the whole panel(3CURSES) page, bestie 💖 this was ncurses version 6.4, patch 20221231 — the date on the tin, iconic behavior, no cap. go stack those panels, you absolute legend 🌸🦋✨