xref: /freebsd/contrib/ncurses/TO-DO (revision a90b9d0159070121c221b966469c3e36d912bf82)
1-------------------------------------------------------------------------------
2-- Copyright 2020 Thomas E. Dickey                                           --
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28-------------------------------------------------------------------------------
29-- $Id: TO-DO,v 1.58 2020/02/02 23:34:34 tom Exp $
30-------------------------------------------------------------------------------
31
32SHORT-TERM TO-DO ITEMS:
33
34Known Problems:
35
36+ libtool does not work with GNAT.
37
38+ The screen optimization has been tested only in an ad hoc manner.  We should
39  develop a good set of regression tests to cover lib_doupdate.c and
40  lib_mvcur.c.
41
42+ Magic cookie support (for nonzero xmc values) does not work, since the logic
43  does not take into account refresh.  Also, the initial optimize does not
44  adjust the current location when a cookie is emitted.
45
46+ Scrolling optimization has holes:  for example, it forces repaints of the
47  screen between calls to refresh().
48
49+ SVr4 uses slightly different rules for determining when softkeys are shown.
50  For example, they are initially displayed (before the ncurses 'e' test
51  activates them), and a touchwin can apparently also force them to be
52  displayed.
53
54+ The code departs from perfect 8-bit cleanness in one respect; you cannot
55  specify a character \200 as part of a capability string, because the
56  terminfo library interprets \200 as a request to embed NUL (\000) at that
57  point.  This is a legacy terminfo property we can't mess with.
58
59+ The window classes defined in the c++ subdirectory need documentation.  Some
60  C++ programmer could earn a lot of good karma by doing this...
61
62+ vid_attr() should support the set_a_attributes (sgr1) string, but does not.
63  There appear to be no terminals that require that functionality.
64
65+ the configure --disable-ext-funcs option does not work for Ada95 tree.
66
67+ the --with-pthread configuration builds for Cygwin, but does not work
68  properly (test/worm.c shows all of the worms in the same location).
69
70+ the --enable-rpath configure option builds for the corresponding platforms;
71  however combining it with --with-ticlib and --with-termlib does not always
72  produce libraries that can be run without setting environment variables.
73  Building those with libtool does not work either.  (This is a problem with
74  the BSD platforms).
75
76+ more work is needed to make the MinGW port support ordinary terminals.
77
78Portability (or lack thereof):
79
80+ Users of older System V UNIXes (but not Solaris, and probably not SVr4) may
81  trip over a known problem with the signal-handling code which causes abrupt
82  termination of ncurses applications following resume from a ^Z suspend (this
83  problem was first seen running lynx).  You will not see this problem if you
84  are using one of the 4.4BSD derivatives like such as, NetBSD, or BSDI, or
85  systems using that convention.  For details, see the analysis in the header
86  comment of ncurses/tty/lib_tstp.c .
87
88+ In theory, vwprintw and vwscanf are supposed to use the older varargs.h
89  interface for handling variadic argument lists (and are deprecated by X/Open
90  for that reason).  Many newer systems do no have varargs.h, instead they have
91  only the newer X/Open-standard stdargs.h equivalent.  So these functions use
92  stdargs instead.  This is unlikely to be a problem unless you're building
93  ncurses on a System V old enough to only have varargs.h.  (Solaris 2.5.1 used
94  the stdarg.h binding as well).
95
96+ If you're using a system old enough not to have a native vsscanf(3) in its
97  library, vwscanw() will not work.  If you want to fix this, add an
98  implementation to ncurses/vsscanf.c.
99
100+ The C++ binding fails to build with a few C++ compilers.
101
102+ terminfo.5 does not format with the SunOS (and most other platform's) tbl
103  utility because it relies on a diversion for each table entry.  Get the
104  groff package.
105
106Untested features:
107
108+ The code for the HP color model using set_color_pair is untested.
109
110+ The code for handling soft labels on a terminal type with built-in support
111  for them (num_labels > 0, label_height, label_width, label_format, label_off,
112  label_on, plab_norm, lab_f*) has not been tested.  The label_format and
113  lab_f* capabilities aren't presently used.
114
115LONGER-TERM TO-DO ITEMS:
116
1171. Extended COSE conformance
118
119There is an XPG4 standard released in 1996 which describes a superset
120of the SVr4 API.  The library is BASE conformant with this standard.
121We would like to make ncurses fully conformant at the EXTENDED level
122supporting internationalization.
123
1242. DOS port
125
126Only a few of the files in the library depend on the terminfo format.
127It should be possible to further kernelize the package, then rewrite
128a small number of core files to produce a functionally-compatible
129port that would do updates to a memory-mapped screen area.  The first
130result of this would be a DOS port.
131
1323. X port
133
134It would be nice if ncurses could recognize when it was running under X and
135maintain its own window.  With this feature, all ncurses programs would
136automatically become X programs.  The challenge is to handle resize events
137properly.
138
1394. Unused capabilities
140
141The currently unused capabilities fall naturally into several groups:
142
143A. Status-line capabilities:
144
145	Booleans: has_status_line, status_line_esc_ok.
146	Numerics: width_status_line.
147	Strings: dis_status_line, from_status_line, to_status_line.
148
149System V Release 1 curses made no use of these at all.  SVr4's use, if
150any, is unknown.  From the AT&T termcap file it looks like curses, in general,
151shouldn't use them; terminal variants with status lines have their line count
152decremented by 1, suggesting that curses is supposed to leave the status line
153alone.
154
155B. Printer capabilities:
156
157	Boolean: col_addr_glitch, cr_cancels_micro_mode, has_print_wheel,
158		row_addr_glitch, semi_auto_right_margin, cpi_changes_res,
159		lpi_changes_res.
160	Numeric: buffer_capacity, dot_horz_spacing, dot_vert_spacing,
161		max_micro_address, max_micro_jump, micro_col_size,
162		micro_line_size, number_of_pins, output_res_char,
163		output_res_line, output_res_horz_inch, print_rate,
164		wide_char_size, bit_image_entwining, bit_image_type.
165	String: down_half_line, form_feed, up_half_line, set_left_margin,
166		set_right_margin, clear_margins, change_char_pitch
167		... set_page_length (all the SVr4 printer caps),
168
169Curses doesn't use these.
170
171C. Printer-control capabilities:
172
173	Boolean: prtr_silent.
174	Strings: print_screen, prtr_on, prtr_off, prtr_non.
175
176Curses doesn't use these.
177
178D. Dialer strings:
179
180	Strings: hangup, dial_phone, quick_dial, tone, pulse, flash_hook,
181		fixed_pause, wait_tone.
182
183Curses doesn't use these.
184
185E. Window and virtual-terminal capabilities:
186
187	Numerics: maximum_windows, virtual_terminal.
188	Strings: req_for_input, create_window, goto_window, set_window.
189
190These seem to be fossils from some AT&T experiments on character-based
191window systems that never escaped the lab.  The virtual_terminal cap had
192something to do with building terminal emulations into tty line disciplines.
193
194F. Unused VDT capabilities:
195
196	Booleans: erase_overstrike, has_meta_key, insert_null_glitch,
197		move_insert, dest_tabs_magic_smso, transparent_underline,
198		needs_xon_xoff, hard_cursor.
199	Numerics: lines_of_memory, buttons.
200	Strings: pkey_key, pkey_local, pkey_xmit, underline_char,
201		enter_xon_mode,	exit_xon_mode, xon_character, xoff_character,
202		display_clock, remove_clock, user[0-5], display_pc_char,
203		enter_scancode_mode, exit_scancode_mode, pc_term_options,
204		scancode_escape, alt_scancode_esc.
205
206These are the potentially important ones for ncurses.  Notes:
207
208	i) ncurses doesn't need move_insert; it never uses cup/hpa/vpa while
209		insert_mode is on.
210
211	ii) We probably don't care about dest_tabs_magic_smso; only
212		Telerays used it and they're all long obsolete.
213
214-- vile:txtmode
215