2 A Hacker's Guide to NCURSES
7 * Objective of the Package
9 + How to Design Extensions
10 * Portability and Configuration
11 * Documentation Conventions
13 * A Tour of the Ncurses Library
18 + Output and Screen Updating
19 * The Forms and Menu Libraries
20 * A Tour of the Terminfo Compiler
21 + Translation of Non-use Capabilities
22 + Use Capability Resolution
23 + Source-Form Translation
25 * Style Tips for Developers
30 This document is a hacker's tour of the ncurses library and utilities.
31 It discusses design philosophy, implementation methods, and the
32 conventions used for coding and documentation. It is recommended
33 reading for anyone who is interested in porting, extending or
34 improving the package.
36 Objective of the Package
38 The objective of the ncurses package is to provide a free software API
39 for character-cell terminals and terminal emulators with the following
41 * Source-compatible with historical curses implementations
42 (including the original BSD curses and System V curses.
43 * Conformant with the XSI Curses standard issued as part of XPG4 by
45 * High-quality -- stable and reliable code, wide portability, good
46 packaging, superior documentation.
47 * Featureful -- should eliminate as much of the drudgery of C
48 interface programming as possible, freeing programmers to think at
49 a higher level of design.
51 These objectives are in priority order. So, for example, source
52 compatibility with older version must trump featurefulness -- we
53 cannot add features if it means breaking the portion of the API
54 corresponding to historical curses versions.
58 We used System V curses as a model, reverse-engineering their API, in
59 order to fulfill the first two objectives.
61 System V curses implementations can support BSD curses programs with
62 just a recompilation, so by capturing the System V API we also capture
65 More importantly for the future, the XSI Curses standard issued by
66 X/Open is explicitly and closely modeled on System V. So conformance
67 with System V took us most of the way to base-level XSI conformance.
69 How to Design Extensions
71 The third objective (standards conformance) requires that it be easy
72 to condition source code using ncurses so that the absence of
73 nonstandard extensions does not break the code.
75 Accordingly, we have a policy of associating with each nonstandard
76 extension a feature macro, so that ncurses client code can use this
77 macro to condition in or out the code that requires the ncurses
80 For example, there is a macro NCURSES_MOUSE_VERSION which XSI Curses
81 does not define, but which is defined in the ncurses library header.
82 You can use this to condition the calls to the mouse API calls.
84 Portability and Configuration
86 Code written for ncurses may assume an ANSI-standard C compiler and
87 POSIX-compatible OS interface. It may also assume the presence of a
88 System-V-compatible select(2) call.
90 We encourage (but do not require) developers to make the code friendly
91 to less-capable UNIX environments wherever possible.
93 We encourage developers to support OS-specific optimizations and
94 methods not available under POSIX/ANSI, provided only that:
95 * All such code is properly conditioned so the build process does
96 not attempt to compile it under a plain ANSI/POSIX environment.
97 * Adding such implementation methods does not introduce
98 incompatibilities in the ncurses API between platforms.
100 We use GNU autoconf(1) as a tool to deal with portability issues. The
101 right way to leverage an OS-specific feature is to modify the autoconf
102 specification files (configure.in and aclocal.m4) to set up a new
103 feature macro, which you then use to condition your code.
105 Documentation Conventions
107 There are three kinds of documentation associated with this package.
108 Each has a different preferred format:
109 * Package-internal files (README, INSTALL, TO-DO etc.)
111 * Everything else (i.e., narrative documentation).
113 Our conventions are simple:
114 1. Maintain package-internal files in plain text. The expected viewer
115 for them more(1) or an editor window; there's no point in
117 2. Mark up manual pages in the man macros. These have to be viewable
118 through traditional man(1) programs.
119 3. Write everything else in HTML.
121 When in doubt, HTMLize a master and use lynx(1) to generate plain
122 ASCII (as we do for the announcement document).
124 The reason for choosing HTML is that it's (a) well-adapted for on-line
125 browsing through viewers that are everywhere; (b) more easily readable
126 as plain text than most other mark-ups, if you don't have a viewer;
127 and (c) carries enough information that you can generate a
128 nice-looking printed version from it. Also, of course, it make
129 exporting things like the announcement document to WWW pretty trivial.
133 The reporting address for bugs is bug-ncurses@gnu.org. This is a
134 majordomo list; to join, write to bug-ncurses-request@gnu.org with a
135 message containing the line:
136 subscribe <name>@<host.domain>
138 The ncurses code is maintained by a small group of volunteers. While
139 we try our best to fix bugs promptly, we simply don't have a lot of
140 hours to spend on elementary hand-holding. We rely on intelligent
141 cooperation from our users. If you think you have found a bug in
142 ncurses, there are some steps you can take before contacting us that
143 will help get the bug fixed quickly.
145 In order to use our bug-fixing time efficiently, we put people who
146 show us they've taken these steps at the head of our queue. This means
147 that if you don't, you'll probably end up at the tail end and have to
149 1. Develop a recipe to reproduce the bug.
150 Bugs we can reproduce are likely to be fixed very quickly, often
151 within days. The most effective single thing you can do to get a
152 quick fix is develop a way we can duplicate the bad behavior --
153 ideally, by giving us source for a small, portable test program
154 that breaks the library. (Even better is a keystroke recipe using
155 one of the test programs provided with the distribution.)
156 2. Try to reproduce the bug on a different terminal type.
157 In our experience, most of the behaviors people report as library
158 bugs are actually due to subtle problems in terminal descriptions.
159 This is especially likely to be true if you're using a traditional
160 asynchronous terminal or PC-based terminal emulator, rather than
161 xterm or a UNIX console entry.
162 It's therefore extremely helpful if you can tell us whether or not
163 your problem reproduces on other terminal types. Usually you'll
164 have both a console type and xterm available; please tell us
165 whether or not your bug reproduces on both.
166 If you have xterm available, it is also good to collect xterm
167 reports for different window sizes. This is especially true if you
168 normally use an unusual xterm window size -- a surprising number
169 of the bugs we've seen are either triggered or masked by these.
170 3. Generate and examine a trace file for the broken behavior.
171 Recompile your program with the debugging versions of the
172 libraries. Insert a trace() call with the argument set to
173 TRACE_UPDATE. (See "Writing Programs with NCURSES" for details on
174 trace levels.) Reproduce your bug, then look at the trace file to
175 see what the library was actually doing.
176 Another frequent cause of apparent bugs is application coding
177 errors that cause the wrong things to be put on the virtual
178 screen. Looking at the virtual-screen dumps in the trace file will
179 tell you immediately if this is happening, and save you from the
180 possible embarrassment of being told that the bug is in your code
181 and is your problem rather than ours.
182 If the virtual-screen dumps look correct but the bug persists,
183 it's possible to crank up the trace level to give more and more
184 information about the library's update actions and the control
185 sequences it issues to perform them. The test directory of the
186 distribution contains a tool for digesting these logs to make them
187 less tedious to wade through.
188 Often you'll find terminfo problems at this stage by noticing that
189 the escape sequences put out for various capabilities are wrong.
190 If not, you're likely to learn enough to be able to characterize
191 any bug in the screen-update logic quite exactly.
192 4. Report details and symptoms, not just interpretations.
193 If you do the preceding two steps, it is very likely that you'll
194 discover the nature of the problem yourself and be able to send us
195 a fix. This will create happy feelings all around and earn you
196 good karma for the first time you run into a bug you really can't
197 characterize and fix yourself.
198 If you're still stuck, at least you'll know what to tell us.
199 Remember, we need details. If you guess about what is safe to
200 leave out, you are too likely to be wrong.
201 If your bug produces a bad update, include a trace file. Try to
202 make the trace at the least voluminous level that pins down the
203 bug. Logs that have been through tracemunch are OK, it doesn't
204 throw away any information (actually they're better than
205 un-munched ones because they're easier to read).
206 If your bug produces a core-dump, please include a symbolic stack
207 trace generated by gdb(1) or your local equivalent.
208 Tell us about every terminal on which you've reproduced the bug --
209 and every terminal on which you can't. Ideally, sent us terminfo
210 sources for all of these (yours might differ from ours).
211 Include your ncurses version and your OS/machine type, of course!
212 You can find your ncurses version in the curses.h file.
214 If your problem smells like a logic error or in cursor movement or
215 scrolling or a bad capability, there are a couple of tiny test frames
216 for the library algorithms in the progs directory that may help you
217 isolate it. These are not part of the normal build, but do have their
218 own make productions.
220 The most important of these is mvcur, a test frame for the
221 cursor-movement optimization code. With this program, you can see
222 directly what control sequences will be emitted for any given cursor
223 movement or scroll/insert/delete operations. If you think you've got a
224 bad capability identified, you can disable it and test again. The
225 program is command-driven and has on-line help.
227 If you think the vertical-scroll optimization is broken, or just want
228 to understand how it works better, build hashmap and read the header
229 comments of hardscroll.c and hashmap.c; then try it out. You can also
230 test the hardware-scrolling optimization separately with hardscroll.
232 There's one other interactive tester, tctest, that exercises
233 translation between termcap and terminfo formats. If you have a
234 serious need to run this, you probably belong on our development team!
236 A Tour of the Ncurses Library
240 Most of the library is superstructure -- fairly trivial convenience
241 interfaces to a small set of basic functions and data structures used
242 to manipulate the virtual screen (in particular, none of this code
243 does any I/O except through calls to more fundamental modules
244 described below). The files
246 lib_addch.c lib_bkgd.c lib_box.c lib_chgat.c lib_clear.c
247 lib_clearok.c lib_clrbot.c lib_clreol.c lib_colorset.c lib_data.c
248 lib_delch.c lib_delwin.c lib_echo.c lib_erase.c lib_gen.c
249 lib_getstr.c lib_hline.c lib_immedok.c lib_inchstr.c lib_insch.c
250 lib_insdel.c lib_insstr.c lib_instr.c lib_isendwin.c lib_keyname.c
251 lib_leaveok.c lib_move.c lib_mvwin.c lib_overlay.c lib_pad.c
252 lib_printw.c lib_redrawln.c lib_scanw.c lib_screen.c lib_scroll.c
253 lib_scrollok.c lib_scrreg.c lib_set_term.c lib_slk.c
254 lib_slkatr_set.c lib_slkatrof.c lib_slkatron.c lib_slkatrset.c
255 lib_slkattr.c lib_slkclear.c lib_slkcolor.c lib_slkinit.c
256 lib_slklab.c lib_slkrefr.c lib_slkset.c lib_slktouch.c lib_touch.c
257 lib_unctrl.c lib_vline.c lib_wattroff.c lib_wattron.c lib_window.c
259 are all in this category. They are very unlikely to need change,
260 barring bugs or some fundamental reorganization in the underlying data
263 These files are used only for debugging support:
265 lib_trace.c lib_traceatr.c lib_tracebits.c lib_tracechr.c
266 lib_tracedmp.c lib_tracemse.c trace_buf.c
268 It is rather unlikely you will ever need to change these, unless you
269 want to introduce a new debug trace level for some reasoon.
271 There is another group of files that do direct I/O via tputs(),
272 computations on the terminal capabilities, or queries to the OS
273 environment, but nevertheless have only fairly low complexity. These
276 lib_acs.c lib_beep.c lib_color.c lib_endwin.c lib_initscr.c
277 lib_longname.c lib_newterm.c lib_options.c lib_termcap.c lib_ti.c
278 lib_tparm.c lib_tputs.c lib_vidattr.c read_entry.c.
280 They are likely to need revision only if ncurses is being ported to an
281 environment without an underlying terminfo capability representation.
283 These files have serious hooks into the tty driver and signal
286 lib_kernel.c lib_baudrate.c lib_raw.c lib_tstp.c lib_twait.c
288 If you run into porting snafus moving the package to another UNIX, the
289 problem is likely to be in one of these files. The file lib_print.c
290 uses sleep(2) and also falls in this category.
292 Almost all of the real work is done in the files
294 hardscroll.c hashmap.c lib_addch.c lib_doupdate.c lib_getch.c
295 lib_mouse.c lib_mvcur.c lib_refresh.c lib_setup.c lib_vidattr.c
297 Most of the algorithmic complexity in the library lives in these
298 files. If there is a real bug in ncurses itself, it's probably here.
299 We'll tour some of these files in detail below (see The Engine Room).
301 Finally, there is a group of files that is actually most of the
302 terminfo compiler. The reason this code lives in the ncurses library
303 is to support fallback to /etc/termcap. These files include
305 alloc_entry.c captoinfo.c comp_captab.c comp_error.c comp_hash.c
306 comp_parse.c comp_scan.c parse_entry.c read_termcap.c write_entry.c
308 We'll discuss these in the compiler tour.
314 All ncurses input funnels through the function wgetch(), defined in
315 lib_getch.c. This function is tricky; it has to poll for keyboard and
316 mouse events and do a running match of incoming input against the set
317 of defined special keys.
319 The central data structure in this module is a FIFO queue, used to
320 match multiple-character input sequences against special-key
321 capabilities; also to implement pushback via ungetch().
323 The wgetch() code distinguishes between function key sequences and the
324 same sequences typed manually by doing a timed wait after each input
325 character that could lead a function key sequence. If the entire
326 sequence takes less than 1 second, it is assumed to have been
327 generated by a function key press.
329 Hackers bruised by previous encounters with variant select(2) calls
330 may find the code in lib_twait.c interesting. It deals with the
331 problem that some BSD selects don't return a reliable time-left value.
332 The function timed_wait() effectively simulates a System V select.
336 If the mouse interface is active, wgetch() polls for mouse events each
337 call, before it goes to the keyboard for input. It is up to
338 lib_mouse.c how the polling is accomplished; it may vary for different
341 Under xterm, however, mouse event notifications come in via the
342 keyboard input stream. They are recognized by having the kmous
343 capability as a prefix. This is kind of klugey, but trying to wire in
344 recognition of a mouse key prefix without going through the
345 function-key machinery would be just too painful, and this turns out
346 to imply having the prefix somewhere in the function-key capabilities
347 at terminal-type initialization.
349 This kluge only works because kmous isn't actually used by any
350 historic terminal type or curses implementation we know of. Best guess
351 is it's a relic of some forgotten experiment in-house at Bell Labs
352 that didn't leave any traces in the publicly-distributed System V
353 terminfo files. If System V or XPG4 ever gets serious about using it
354 again, this kluge may have to change.
356 Here are some more details about mouse event handling:
358 The lib_mouse()code is logically split into a lower level that accepts
359 event reports in a device-dependent format and an upper level that
360 parses mouse gestures and filters events. The mediating data structure
361 is a circular queue of event structures.
363 Functionally, the lower level's job is to pick up primitive events and
364 put them on the circular queue. This can happen in one of two ways:
365 either (a) _nc_mouse_event() detects a series of incoming mouse
366 reports and queues them, or (b) code in lib_getch.c detects the kmous
367 prefix in the keyboard input stream and calls _nc_mouse_inline to
368 queue up a series of adjacent mouse reports.
370 In either case, _nc_mouse_parse() should be called after the series is
371 accepted to parse the digested mouse reports (low-level events) into a
372 gesture (a high-level or composite event).
374 Output and Screen Updating
376 With the single exception of character echoes during a wgetnstr() call
377 (which simulates cooked-mode line editing in an ncurses window), the
378 library normally does all its output at refresh time.
380 The main job is to go from the current state of the screen (as
381 represented in the curscr window structure) to the desired new state
382 (as represented in the newscr window structure), while doing as little
385 The brains of this operation are the modules hashmap.c, hardscroll.c
386 and lib_doupdate.c; the latter two use lib_mvcur.c. Essentially, what
387 happens looks like this:
389 The hashmap.c module tries to detect vertical motion changes between
390 the real and virtual screens. This information is represented by the
391 oldindex members in the newscr structure. These are modified by
392 vertical-motion and clear operations, and both are re-initialized
393 after each update. To this change-journalling information, the hashmap
394 code adds deductions made using a modified Heckel algorithm on hash
395 values generated from the line contents.
397 The hardscroll.c module computes an optimum set of scroll, insertion,
398 and deletion operations to make the indices match. It calls
399 _nc_mvcur_scrolln() in lib_mvcur.c to do those motions.
401 Then lib_doupdate.c goes to work. Its job is to do line-by-line
402 transformations of curscr lines to newscr lines. Its main tool is the
403 routine mvcur() in lib_mvcur.c. This routine does cursor-movement
404 optimization, attempting to get from given screen location A to given
405 location B in the fewest output characters posible.
407 If you want to work on screen optimizations, you should use the fact
408 that (in the trace-enabled version of the library) enabling the
409 TRACE_TIMES trace level causes a report to be emitted after each
410 screen update giving the elapsed time and a count of characters
411 emitted during the update. You can use this to tell when an update
412 optimization improves efficiency.
414 In the trace-enabled version of the library, it is also possible to
415 disable and re-enable various optimizations at runtime by tweaking the
416 variable _nc_optimize_enable. See the file include/curses.h.in for
417 mask values, near the end.
419 The Forms and Menu Libraries
421 The forms and menu libraries should work reliably in any environment
422 you can port ncurses to. The only portability issue anywhere in them
423 is what flavor of regular expressions the built-in form field type
424 TYPE_REGEXP will recognize.
426 The configuration code prefers the POSIX regex facility, modeled on
427 System V's, but will settle for BSD regexps if the former isn't
430 Historical note: the panels code was written primarily to assist in
431 porting u386mon 2.0 (comp.sources.misc v14i001-4) to systems lacking
432 panels support; u386mon 2.10 and beyond use it. This version has been
433 slightly cleaned up for ncurses.
435 A Tour of the Terminfo Compiler
437 The ncurses implementation of tic is rather complex internally; it has
438 to do a trying combination of missions. This starts with the fact
439 that, in addition to its normal duty of compiling terminfo sources
440 into loadable terminfo binaries, it has to be able to handle termcap
441 syntax and compile that too into terminfo entries.
443 The implementation therefore starts with a table-driven, dual-mode
444 lexical analyzer (in comp_scan.c). The lexer chooses its mode (termcap
445 or terminfo) based on the first `,' or `:' it finds in each entry. The
446 lexer does all the work of recognizing capability names and values;
447 the grammar above it is trivial, just "parse entries till you run out
450 Translation of Non-use Capabilities
452 Translation of most things besides use capabilities is pretty
453 straightforward. The lexical analyzer's tokenizer hands each
454 capability name to a hash function, which drives a table lookup. The
455 table entry yields an index which is used to look up the token type in
456 another table, and controls interpretation of the value.
458 One possibly interesting aspect of the implementation is the way the
459 compiler tables are initialized. All the tables are generated by
460 various awk/sed/sh scripts from a master table include/Caps; these
461 scripts actually write C initializers which are linked to the
462 compiler. Furthermore, the hash table is generated in the same way, so
463 it doesn't have to be generated at compiler startup time (another
464 benefit of this organization is that the hash table can be in
465 shareable text space).
467 Thus, adding a new capability is usually pretty trivial, just a matter
468 of adding one line to the include/Caps file. We'll have more to say
469 about this in the section on Source-Form Translation.
471 Use Capability Resolution
473 The background problem that makes tic tricky isn't the capability
474 translation itself, it's the resolution of use capabilities. Older
475 versions would not handle forward use references for this reason (that
476 is, a using terminal always had to follow its use target in the source
477 file). By doing this, they got away with a simple implementation
478 tactic; compile everything as it blows by, then resolve uses from
481 This won't do for ncurses. The problem is that that the whole
482 compilation process has to be embeddable in the ncurses library so
483 that it can be called by the startup code to translate termcap entries
484 on the fly. The embedded version can't go promiscuously writing
485 everything it translates out to disk -- for one thing, it will
486 typically be running with non-root permissions.
488 So our tic is designed to parse an entire terminfo file into a
489 doubly-linked circular list of entry structures in-core, and then do
490 use resolution in-memory before writing everything out. This design
491 has other advantages: it makes forward and back use-references equally
492 easy (so we get the latter for free), and it makes checking for name
493 collisions before they're written out easy to do.
495 And this is exactly how the embedded version works. But the
496 stand-alone user-accessible version of tic partly reverts to the
497 historical strategy; it writes to disk (not keeping in core) any entry
498 with no use references.
500 This is strictly a core-economy kluge, implemented because the
501 terminfo master file is large enough that some core-poor systems swap
502 like crazy when you compile it all in memory...there have been reports
503 of this process taking three hours, rather than the twenty seconds or
504 less typical on the author's development box.
506 So. The executable tic passes the entry-parser a hook that immediately
507 writes out the referenced entry if it has no use capabilities. The
508 compiler main loop refrains from adding the entry to the in-core list
509 when this hook fires. If some other entry later needs to reference an
510 entry that got written immediately, that's OK; the resolution code
511 will fetch it off disk when it can't find it in core.
513 Name collisions will still be detected, just not as cleanly. The
514 write_entry() code complains before overwriting an entry that
515 postdates the time of tic's first call to write_entry(), Thus it will
516 complain about overwriting entries newly made during the tic run, but
517 not about overwriting ones that predate it.
519 Source-Form Translation
521 Another use of tic is to do source translation between various termcap
522 and terminfo formats. There are more variants out there than you might
523 think; the ones we know about are described in the captoinfo(1) manual
526 The translation output code (dump_entry() in ncurses/dump_entry.c) is
527 shared with the infocmp(1) utility. It takes the same internal
528 representation used to generate the binary form and dumps it to
529 standard output in a specified format.
531 The include/Caps file has a header comment describing ways you can
532 specify source translations for nonstandard capabilities just by
533 altering the master table. It's possible to set up capability aliasing
534 or tell the compiler to plain ignore a given capability without
535 writing any C code at all.
537 For circumstances where you need to do algorithmic translation, there
538 are functions in parse_entry.c called after the parse of each entry
539 that are specifically intended to encapsulate such translations. This,
540 for example, is where the AIX box1 capability get translated to an
545 The infocmp utility is just a wrapper around the same entry-dumping
546 code used by tic for source translation. Perhaps the one interesting
547 aspect of the code is the use of a predicate function passed in to
548 dump_entry() to control which capabilities are dumped. This is
549 necessary in order to handle both the ordinary De-compilation case and
550 entry difference reporting.
552 The tput and clear utilities just do an entry load followed by a
553 tputs() of a selected capability.
555 Style Tips for Developers
557 See the TO-DO file in the top-level directory of the source
558 distribution for additions that would be particularly useful.
560 The prefix _nc_ should be used on library public functions that are
561 not part of the curses API in order to prevent pollution of the
562 application namespace. If you have to add to or modify the function
563 prototypes in curses.h.in, read ncurses/MKlib_gen.sh first so you can
564 avoid breaking XSI conformance. Please join the ncurses mailing list.
565 See the INSTALL file in the top level of the distribution for details
568 Look for the string FIXME in source files to tag minor bugs and
569 potential problems that could use fixing.
571 Don't try to auto-detect OS features in the main body of the C code.
572 That's the job of the configuration system.
574 To hold down complexity, do make your code data-driven. Especially, if
575 you can drive logic from a table filtered out of include/Caps, do it.
576 If you find you need to augment the data in that file in order to
577 generate the proper table, that's still preferable to ad-hoc code --
578 that's why the fifth field (flags) is there.
584 The following notes are intended to be a first step towards DOS and
585 Macintosh ports of the ncurses libraries.
587 The following library modules are `pure curses'; they operate only on
588 the curses internal structures, do all output through other curses
589 calls (not including tputs() and putp()) and do not call any other
590 UNIX routines such as signal(2) or the stdio library. Thus, they
591 should not need to be modified for single-terminal ports.
593 lib_addch.c lib_addstr.c lib_bkgd.c lib_box.c lib_clear.c
594 lib_clrbot.c lib_clreol.c lib_delch.c lib_delwin.c lib_erase.c
595 lib_inchstr.c lib_insch.c lib_insdel.c lib_insstr.c lib_keyname.c
596 lib_move.c lib_mvwin.c lib_newwin.c lib_overlay.c lib_pad.c
597 lib_printw.c lib_refresh.c lib_scanw.c lib_scroll.c lib_scrreg.c
598 lib_set_term.c lib_touch.c lib_tparm.c lib_tputs.c lib_unctrl.c
601 This module is pure curses, but calls outstr():
605 These modules are pure curses, except that they use tputs() and
608 lib_beep.c lib_color.c lib_endwin.c lib_options.c lib_slk.c
611 This modules assist in POSIX emulation on non-POSIX systems:
616 The following source files will not be needed for a
617 single-terminal-type port.
619 alloc_entry.c captoinfo.c clear.c comp_captab.c comp_error.c
620 comp_hash.c comp_main.c comp_parse.c comp_scan.c dump_entry.c
621 infocmp.c parse_entry.c read_entry.c tput.c write_entry.c
623 The following modules will use open()/read()/write()/close()/lseek()
624 on files, but no other OS calls.
627 used to read/write screen dumps
630 used to write trace data to the logfile
632 Modules that would have to be modified for a port start here:
634 The following modules are `pure curses' but contain assumptions
635 inappropriate for a memory-mapped port.
638 assumes there may be multiple terminals
641 assumes acs_map as a double indirection
644 assumes cursor moves have variable cost
647 assumes there may be multiple terminals
650 assumes there may be multiple terminals
652 The following modules use UNIX-specific calls:
666 various tty-manipulation and system calls
669 various tty-manipulation calls
672 various tty-manipulation calls
675 various tty-manipulation calls
678 signal-manipulation calls
681 gettimeofday(), select().
682 _________________________________________________________________
685 Eric S. Raymond <esr@snark.thyrsus.com>
687 (Note: This is not the bug address!)
projects / ncurses.git / blob