683 lines
32 KiB
Plaintext
683 lines
32 KiB
Plaintext
A Hacker's Guide to NCURSES
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Contents
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* Abstract
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* Objective of the Package
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+ Why System V Curses?
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+ How to Design Extensions
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* Portability and Configuration
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* Documentation Conventions
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* How to Report Bugs
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* A Tour of the Ncurses Library
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+ Library Overview
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+ The Engine Room
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+ Keyboard Input
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+ Mouse Events
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+ Output and Screen Updating
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* The Forms and Menu Libraries
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* A Tour of the Terminfo Compiler
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+ Translation of Non-use Capabilities
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+ Use Capability Resolution
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+ Source-Form Translation
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* Other Utilities
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* Style Tips for Developers
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* Porting Hints
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Abstract
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This document is a hacker's tour of the ncurses library and utilities.
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It discusses design philosophy, implementation methods, and the
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conventions used for coding and documentation. It is recommended
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reading for anyone who is interested in porting, extending or
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improving the package.
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Objective of the Package
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The objective of the ncurses package is to provide a free software API
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for character-cell terminals and terminal emulators with the following
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characteristics:
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* Source-compatible with historical curses implementations
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(including the original BSD curses and System V curses.
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* Conformant with the XSI Curses standard issued as part of XPG4 by
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X/Open.
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* High-quality -- stable and reliable code, wide portability, good
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packaging, superior documentation.
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* Featureful -- should eliminate as much of the drudgery of C
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interface programming as possible, freeing programmers to think at
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a higher level of design.
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These objectives are in priority order. So, for example, source
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compatibility with older version must trump featurefulness -- we
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cannot add features if it means breaking the portion of the API
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corresponding to historical curses versions.
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Why System V Curses?
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We used System V curses as a model, reverse-engineering their API, in
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order to fulfill the first two objectives.
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System V curses implementations can support BSD curses programs with
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just a recompilation, so by capturing the System V API we also capture
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BSD's.
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More importantly for the future, the XSI Curses standard issued by
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X/Open is explicitly and closely modeled on System V. So conformance
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with System V took us most of the way to base-level XSI conformance.
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How to Design Extensions
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The third objective (standards conformance) requires that it be easy
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to condition source code using ncurses so that the absence of
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nonstandard extensions does not break the code.
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Accordingly, we have a policy of associating with each nonstandard
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extension a feature macro, so that ncurses client code can use this
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macro to condition in or out the code that requires the ncurses
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extension.
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For example, there is a macro NCURSES_MOUSE_VERSION which XSI Curses
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does not define, but which is defined in the ncurses library header.
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You can use this to condition the calls to the mouse API calls.
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Portability and Configuration
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Code written for ncurses may assume an ANSI-standard C compiler and
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POSIX-compatible OS interface. It may also assume the presence of a
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System-V-compatible select(2) call.
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We encourage (but do not require) developers to make the code friendly
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to less-capable UNIX environments wherever possible.
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We encourage developers to support OS-specific optimizations and
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methods not available under POSIX/ANSI, provided only that:
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* All such code is properly conditioned so the build process does
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not attempt to compile it under a plain ANSI/POSIX environment.
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* Adding such implementation methods does not introduce
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incompatibilities in the ncurses API between platforms.
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We use GNU autoconf(1) as a tool to deal with portability issues. The
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right way to leverage an OS-specific feature is to modify the autoconf
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specification files (configure.in and aclocal.m4) to set up a new
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feature macro, which you then use to condition your code.
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Documentation Conventions
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There are three kinds of documentation associated with this package.
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Each has a different preferred format:
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* Package-internal files (README, INSTALL, TO-DO etc.)
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* Manual pages.
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* Everything else (i.e., narrative documentation).
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Our conventions are simple:
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1. Maintain package-internal files in plain text. The expected viewer
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for them more(1) or an editor window; there's no point in
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elaborate mark-up.
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2. Mark up manual pages in the man macros. These have to be viewable
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through traditional man(1) programs.
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3. Write everything else in HTML.
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When in doubt, HTMLize a master and use lynx(1) to generate plain
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ASCII (as we do for the announcement document).
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The reason for choosing HTML is that it's (a) well-adapted for on-line
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browsing through viewers that are everywhere; (b) more easily readable
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as plain text than most other mark-ups, if you don't have a viewer;
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and (c) carries enough information that you can generate a
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nice-looking printed version from it. Also, of course, it make
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exporting things like the announcement document to WWW pretty trivial.
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How to Report Bugs
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The reporting address for bugs is bug-ncurses@gnu.org. This is a
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majordomo list; to join, write to bug-ncurses-request@gnu.org with a
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message containing the line:
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subscribe <name>@<host.domain>
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The ncurses code is maintained by a small group of volunteers. While
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we try our best to fix bugs promptly, we simply don't have a lot of
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hours to spend on elementary hand-holding. We rely on intelligent
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cooperation from our users. If you think you have found a bug in
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ncurses, there are some steps you can take before contacting us that
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will help get the bug fixed quickly.
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In order to use our bug-fixing time efficiently, we put people who
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show us they've taken these steps at the head of our queue. This means
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that if you don't, you'll probably end up at the tail end and have to
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wait a while.
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1. Develop a recipe to reproduce the bug.
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Bugs we can reproduce are likely to be fixed very quickly, often
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within days. The most effective single thing you can do to get a
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quick fix is develop a way we can duplicate the bad behavior --
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ideally, by giving us source for a small, portable test program
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that breaks the library. (Even better is a keystroke recipe using
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one of the test programs provided with the distribution.)
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2. Try to reproduce the bug on a different terminal type.
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In our experience, most of the behaviors people report as library
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bugs are actually due to subtle problems in terminal descriptions.
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This is especially likely to be true if you're using a traditional
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asynchronous terminal or PC-based terminal emulator, rather than
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xterm or a UNIX console entry.
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It's therefore extremely helpful if you can tell us whether or not
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your problem reproduces on other terminal types. Usually you'll
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have both a console type and xterm available; please tell us
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whether or not your bug reproduces on both.
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If you have xterm available, it is also good to collect xterm
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reports for different window sizes. This is especially true if you
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normally use an unusual xterm window size -- a surprising number
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of the bugs we've seen are either triggered or masked by these.
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3. Generate and examine a trace file for the broken behavior.
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Recompile your program with the debugging versions of the
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libraries. Insert a trace() call with the argument set to
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TRACE_UPDATE. (See "Writing Programs with NCURSES" for details on
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trace levels.) Reproduce your bug, then look at the trace file to
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see what the library was actually doing.
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Another frequent cause of apparent bugs is application coding
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errors that cause the wrong things to be put on the virtual
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screen. Looking at the virtual-screen dumps in the trace file will
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tell you immediately if this is happening, and save you from the
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possible embarrassment of being told that the bug is in your code
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and is your problem rather than ours.
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If the virtual-screen dumps look correct but the bug persists,
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it's possible to crank up the trace level to give more and more
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information about the library's update actions and the control
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sequences it issues to perform them. The test directory of the
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distribution contains a tool for digesting these logs to make them
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less tedious to wade through.
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Often you'll find terminfo problems at this stage by noticing that
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the escape sequences put out for various capabilities are wrong.
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If not, you're likely to learn enough to be able to characterize
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any bug in the screen-update logic quite exactly.
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4. Report details and symptoms, not just interpretations.
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If you do the preceding two steps, it is very likely that you'll
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discover the nature of the problem yourself and be able to send us
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a fix. This will create happy feelings all around and earn you
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good karma for the first time you run into a bug you really can't
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characterize and fix yourself.
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If you're still stuck, at least you'll know what to tell us.
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Remember, we need details. If you guess about what is safe to
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leave out, you are too likely to be wrong.
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If your bug produces a bad update, include a trace file. Try to
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make the trace at the least voluminous level that pins down the
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bug. Logs that have been through tracemunch are OK, it doesn't
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throw away any information (actually they're better than
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un-munched ones because they're easier to read).
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If your bug produces a core-dump, please include a symbolic stack
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trace generated by gdb(1) or your local equivalent.
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Tell us about every terminal on which you've reproduced the bug --
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and every terminal on which you can't. Ideally, sent us terminfo
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sources for all of these (yours might differ from ours).
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Include your ncurses version and your OS/machine type, of course!
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You can find your ncurses version in the curses.h file.
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If your problem smells like a logic error or in cursor movement or
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scrolling or a bad capability, there are a couple of tiny test frames
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for the library algorithms in the progs directory that may help you
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isolate it. These are not part of the normal build, but do have their
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own make productions.
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The most important of these is mvcur, a test frame for the
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cursor-movement optimization code. With this program, you can see
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directly what control sequences will be emitted for any given cursor
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movement or scroll/insert/delete operations. If you think you've got a
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bad capability identified, you can disable it and test again. The
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program is command-driven and has on-line help.
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If you think the vertical-scroll optimization is broken, or just want
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to understand how it works better, build hashmap and read the header
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comments of hardscroll.c and hashmap.c; then try it out. You can also
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test the hardware-scrolling optimization separately with hardscroll.
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A Tour of the Ncurses Library
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Library Overview
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Most of the library is superstructure -- fairly trivial convenience
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interfaces to a small set of basic functions and data structures used
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to manipulate the virtual screen (in particular, none of this code
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does any I/O except through calls to more fundamental modules
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described below). The files
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lib_addch.c lib_bkgd.c lib_box.c lib_chgat.c lib_clear.c
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lib_clearok.c lib_clrbot.c lib_clreol.c lib_colorset.c lib_data.c
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lib_delch.c lib_delwin.c lib_echo.c lib_erase.c lib_gen.c
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lib_getstr.c lib_hline.c lib_immedok.c lib_inchstr.c lib_insch.c
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lib_insdel.c lib_insstr.c lib_instr.c lib_isendwin.c lib_keyname.c
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lib_leaveok.c lib_move.c lib_mvwin.c lib_overlay.c lib_pad.c
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lib_printw.c lib_redrawln.c lib_scanw.c lib_screen.c lib_scroll.c
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lib_scrollok.c lib_scrreg.c lib_set_term.c lib_slk.c
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lib_slkatr_set.c lib_slkatrof.c lib_slkatron.c lib_slkatrset.c
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lib_slkattr.c lib_slkclear.c lib_slkcolor.c lib_slkinit.c
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lib_slklab.c lib_slkrefr.c lib_slkset.c lib_slktouch.c lib_touch.c
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lib_unctrl.c lib_vline.c lib_wattroff.c lib_wattron.c lib_window.c
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are all in this category. They are very unlikely to need change,
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barring bugs or some fundamental reorganization in the underlying data
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structures.
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These files are used only for debugging support:
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lib_trace.c lib_traceatr.c lib_tracebits.c lib_tracechr.c
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lib_tracedmp.c lib_tracemse.c trace_buf.c
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It is rather unlikely you will ever need to change these, unless you
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want to introduce a new debug trace level for some reasoon.
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There is another group of files that do direct I/O via tputs(),
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computations on the terminal capabilities, or queries to the OS
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environment, but nevertheless have only fairly low complexity. These
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include:
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lib_acs.c lib_beep.c lib_color.c lib_endwin.c lib_initscr.c
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lib_longname.c lib_newterm.c lib_options.c lib_termcap.c lib_ti.c
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lib_tparm.c lib_tputs.c lib_vidattr.c read_entry.c.
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They are likely to need revision only if ncurses is being ported to an
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environment without an underlying terminfo capability representation.
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These files have serious hooks into the tty driver and signal
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facilities:
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lib_kernel.c lib_baudrate.c lib_raw.c lib_tstp.c lib_twait.c
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If you run into porting snafus moving the package to another UNIX, the
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problem is likely to be in one of these files. The file lib_print.c
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uses sleep(2) and also falls in this category.
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Almost all of the real work is done in the files
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hardscroll.c hashmap.c lib_addch.c lib_doupdate.c lib_getch.c
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lib_mouse.c lib_mvcur.c lib_refresh.c lib_setup.c lib_vidattr.c
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Most of the algorithmic complexity in the library lives in these
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files. If there is a real bug in ncurses itself, it's probably here.
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We'll tour some of these files in detail below (see The Engine Room).
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Finally, there is a group of files that is actually most of the
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terminfo compiler. The reason this code lives in the ncurses library
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is to support fallback to /etc/termcap. These files include
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alloc_entry.c captoinfo.c comp_captab.c comp_error.c comp_hash.c
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comp_parse.c comp_scan.c parse_entry.c read_termcap.c write_entry.c
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We'll discuss these in the compiler tour.
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The Engine Room
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Keyboard Input
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All ncurses input funnels through the function wgetch(), defined in
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lib_getch.c. This function is tricky; it has to poll for keyboard and
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mouse events and do a running match of incoming input against the set
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of defined special keys.
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The central data structure in this module is a FIFO queue, used to
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match multiple-character input sequences against special-key
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capabilities; also to implement pushback via ungetch().
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The wgetch() code distinguishes between function key sequences and the
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same sequences typed manually by doing a timed wait after each input
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character that could lead a function key sequence. If the entire
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sequence takes less than 1 second, it is assumed to have been
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generated by a function key press.
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Hackers bruised by previous encounters with variant select(2) calls
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may find the code in lib_twait.c interesting. It deals with the
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problem that some BSD selects don't return a reliable time-left value.
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The function timed_wait() effectively simulates a System V select.
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Mouse Events
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If the mouse interface is active, wgetch() polls for mouse events each
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call, before it goes to the keyboard for input. It is up to
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lib_mouse.c how the polling is accomplished; it may vary for different
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devices.
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Under xterm, however, mouse event notifications come in via the
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keyboard input stream. They are recognized by having the kmous
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capability as a prefix. This is kind of klugey, but trying to wire in
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recognition of a mouse key prefix without going through the
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function-key machinery would be just too painful, and this turns out
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to imply having the prefix somewhere in the function-key capabilities
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at terminal-type initialization.
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This kluge only works because kmous isn't actually used by any
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historic terminal type or curses implementation we know of. Best guess
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is it's a relic of some forgotten experiment in-house at Bell Labs
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that didn't leave any traces in the publicly-distributed System V
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terminfo files. If System V or XPG4 ever gets serious about using it
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again, this kluge may have to change.
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Here are some more details about mouse event handling:
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The lib_mouse()code is logically split into a lower level that accepts
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event reports in a device-dependent format and an upper level that
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parses mouse gestures and filters events. The mediating data structure
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is a circular queue of event structures.
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Functionally, the lower level's job is to pick up primitive events and
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put them on the circular queue. This can happen in one of two ways:
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either (a) _nc_mouse_event() detects a series of incoming mouse
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reports and queues them, or (b) code in lib_getch.c detects the kmous
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prefix in the keyboard input stream and calls _nc_mouse_inline to
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queue up a series of adjacent mouse reports.
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In either case, _nc_mouse_parse() should be called after the series is
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accepted to parse the digested mouse reports (low-level events) into a
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gesture (a high-level or composite event).
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Output and Screen Updating
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With the single exception of character echoes during a wgetnstr() call
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(which simulates cooked-mode line editing in an ncurses window), the
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library normally does all its output at refresh time.
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The main job is to go from the current state of the screen (as
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represented in the curscr window structure) to the desired new state
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(as represented in the newscr window structure), while doing as little
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I/O as possible.
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The brains of this operation are the modules hashmap.c, hardscroll.c
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and lib_doupdate.c; the latter two use lib_mvcur.c. Essentially, what
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happens looks like this:
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The hashmap.c module tries to detect vertical motion changes between
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the real and virtual screens. This information is represented by the
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oldindex members in the newscr structure. These are modified by
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vertical-motion and clear operations, and both are re-initialized
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after each update. To this change-journalling information, the hashmap
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code adds deductions made using a modified Heckel algorithm on hash
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values generated from the line contents.
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The hardscroll.c module computes an optimum set of scroll, insertion,
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and deletion operations to make the indices match. It calls
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_nc_mvcur_scrolln() in lib_mvcur.c to do those motions.
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Then lib_doupdate.c goes to work. Its job is to do line-by-line
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transformations of curscr lines to newscr lines. Its main tool is the
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routine mvcur() in lib_mvcur.c. This routine does cursor-movement
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optimization, attempting to get from given screen location A to given
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location B in the fewest output characters possible.
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If you want to work on screen optimizations, you should use the fact
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that (in the trace-enabled version of the library) enabling the
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TRACE_TIMES trace level causes a report to be emitted after each
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screen update giving the elapsed time and a count of characters
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emitted during the update. You can use this to tell when an update
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optimization improves efficiency.
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In the trace-enabled version of the library, it is also possible to
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disable and re-enable various optimizations at runtime by tweaking the
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variable _nc_optimize_enable. See the file include/curses.h.in for
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mask values, near the end.
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The Forms and Menu Libraries
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The forms and menu libraries should work reliably in any environment
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you can port ncurses to. The only portability issue anywhere in them
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is what flavor of regular expressions the built-in form field type
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TYPE_REGEXP will recognize.
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The configuration code prefers the POSIX regex facility, modeled on
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System V's, but will settle for BSD regexps if the former isn't
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available.
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Historical note: the panels code was written primarily to assist in
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porting u386mon 2.0 (comp.sources.misc v14i001-4) to systems lacking
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panels support; u386mon 2.10 and beyond use it. This version has been
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slightly cleaned up for ncurses.
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A Tour of the Terminfo Compiler
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The ncurses implementation of tic is rather complex internally; it has
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to do a trying combination of missions. This starts with the fact
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that, in addition to its normal duty of compiling terminfo sources
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into loadable terminfo binaries, it has to be able to handle termcap
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syntax and compile that too into terminfo entries.
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The implementation therefore starts with a table-driven, dual-mode
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lexical analyzer (in comp_scan.c). The lexer chooses its mode (termcap
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or terminfo) based on the first `,' or `:' it finds in each entry. The
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lexer does all the work of recognizing capability names and values;
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the grammar above it is trivial, just "parse entries till you run out
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of file".
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Translation of Non-use Capabilities
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Translation of most things besides use capabilities is pretty
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straightforward. The lexical analyzer's tokenizer hands each
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capability name to a hash function, which drives a table lookup. The
|
|
table entry yields an index which is used to look up the token type in
|
|
another table, and controls interpretation of the value.
|
|
|
|
One possibly interesting aspect of the implementation is the way the
|
|
compiler tables are initialized. All the tables are generated by
|
|
various awk/sed/sh scripts from a master table include/Caps; these
|
|
scripts actually write C initializers which are linked to the
|
|
compiler. Furthermore, the hash table is generated in the same way, so
|
|
it doesn't have to be generated at compiler startup time (another
|
|
benefit of this organization is that the hash table can be in
|
|
shareable text space).
|
|
|
|
Thus, adding a new capability is usually pretty trivial, just a matter
|
|
of adding one line to the include/Caps file. We'll have more to say
|
|
about this in the section on Source-Form Translation.
|
|
|
|
Use Capability Resolution
|
|
|
|
The background problem that makes tic tricky isn't the capability
|
|
translation itself, it's the resolution of use capabilities. Older
|
|
versions would not handle forward use references for this reason (that
|
|
is, a using terminal always had to follow its use target in the source
|
|
file). By doing this, they got away with a simple implementation
|
|
tactic; compile everything as it blows by, then resolve uses from
|
|
compiled entries.
|
|
|
|
This won't do for ncurses. The problem is that that the whole
|
|
compilation process has to be embeddable in the ncurses library so
|
|
that it can be called by the startup code to translate termcap entries
|
|
on the fly. The embedded version can't go promiscuously writing
|
|
everything it translates out to disk -- for one thing, it will
|
|
typically be running with non-root permissions.
|
|
|
|
So our tic is designed to parse an entire terminfo file into a
|
|
doubly-linked circular list of entry structures in-core, and then do
|
|
use resolution in-memory before writing everything out. This design
|
|
has other advantages: it makes forward and back use-references equally
|
|
easy (so we get the latter for free), and it makes checking for name
|
|
collisions before they're written out easy to do.
|
|
|
|
And this is exactly how the embedded version works. But the
|
|
stand-alone user-accessible version of tic partly reverts to the
|
|
historical strategy; it writes to disk (not keeping in core) any entry
|
|
with no use references.
|
|
|
|
This is strictly a core-economy kluge, implemented because the
|
|
terminfo master file is large enough that some core-poor systems swap
|
|
like crazy when you compile it all in memory...there have been reports
|
|
of this process taking three hours, rather than the twenty seconds or
|
|
less typical on the author's development box.
|
|
|
|
So. The executable tic passes the entry-parser a hook that immediately
|
|
writes out the referenced entry if it has no use capabilities. The
|
|
compiler main loop refrains from adding the entry to the in-core list
|
|
when this hook fires. If some other entry later needs to reference an
|
|
entry that got written immediately, that's OK; the resolution code
|
|
will fetch it off disk when it can't find it in core.
|
|
|
|
Name collisions will still be detected, just not as cleanly. The
|
|
write_entry() code complains before overwriting an entry that
|
|
postdates the time of tic's first call to write_entry(), Thus it will
|
|
complain about overwriting entries newly made during the tic run, but
|
|
not about overwriting ones that predate it.
|
|
|
|
Source-Form Translation
|
|
|
|
Another use of tic is to do source translation between various termcap
|
|
and terminfo formats. There are more variants out there than you might
|
|
think; the ones we know about are described in the captoinfo(1) manual
|
|
page.
|
|
|
|
The translation output code (dump_entry() in ncurses/dump_entry.c) is
|
|
shared with the infocmp(1) utility. It takes the same internal
|
|
representation used to generate the binary form and dumps it to
|
|
standard output in a specified format.
|
|
|
|
The include/Caps file has a header comment describing ways you can
|
|
specify source translations for nonstandard capabilities just by
|
|
altering the master table. It's possible to set up capability aliasing
|
|
or tell the compiler to plain ignore a given capability without
|
|
writing any C code at all.
|
|
|
|
For circumstances where you need to do algorithmic translation, there
|
|
are functions in parse_entry.c called after the parse of each entry
|
|
that are specifically intended to encapsulate such translations. This,
|
|
for example, is where the AIX box1 capability get translated to an
|
|
acsc string.
|
|
|
|
Other Utilities
|
|
|
|
The infocmp utility is just a wrapper around the same entry-dumping
|
|
code used by tic for source translation. Perhaps the one interesting
|
|
aspect of the code is the use of a predicate function passed in to
|
|
dump_entry() to control which capabilities are dumped. This is
|
|
necessary in order to handle both the ordinary De-compilation case and
|
|
entry difference reporting.
|
|
|
|
The tput and clear utilities just do an entry load followed by a
|
|
tputs() of a selected capability.
|
|
|
|
Style Tips for Developers
|
|
|
|
See the TO-DO file in the top-level directory of the source
|
|
distribution for additions that would be particularly useful.
|
|
|
|
The prefix _nc_ should be used on library public functions that are
|
|
not part of the curses API in order to prevent pollution of the
|
|
application namespace. If you have to add to or modify the function
|
|
prototypes in curses.h.in, read ncurses/MKlib_gen.sh first so you can
|
|
avoid breaking XSI conformance. Please join the ncurses mailing list.
|
|
See the INSTALL file in the top level of the distribution for details
|
|
on the list.
|
|
|
|
Look for the string FIXME in source files to tag minor bugs and
|
|
potential problems that could use fixing.
|
|
|
|
Don't try to auto-detect OS features in the main body of the C code.
|
|
That's the job of the configuration system.
|
|
|
|
To hold down complexity, do make your code data-driven. Especially, if
|
|
you can drive logic from a table filtered out of include/Caps, do it.
|
|
If you find you need to augment the data in that file in order to
|
|
generate the proper table, that's still preferable to ad-hoc code --
|
|
that's why the fifth field (flags) is there.
|
|
|
|
Have fun!
|
|
|
|
Porting Hints
|
|
|
|
The following notes are intended to be a first step towards DOS and
|
|
Macintosh ports of the ncurses libraries.
|
|
|
|
The following library modules are `pure curses'; they operate only on
|
|
the curses internal structures, do all output through other curses
|
|
calls (not including tputs() and putp()) and do not call any other
|
|
UNIX routines such as signal(2) or the stdio library. Thus, they
|
|
should not need to be modified for single-terminal ports.
|
|
|
|
lib_addch.c lib_addstr.c lib_bkgd.c lib_box.c lib_clear.c
|
|
lib_clrbot.c lib_clreol.c lib_delch.c lib_delwin.c lib_erase.c
|
|
lib_inchstr.c lib_insch.c lib_insdel.c lib_insstr.c lib_keyname.c
|
|
lib_move.c lib_mvwin.c lib_newwin.c lib_overlay.c lib_pad.c
|
|
lib_printw.c lib_refresh.c lib_scanw.c lib_scroll.c lib_scrreg.c
|
|
lib_set_term.c lib_touch.c lib_tparm.c lib_tputs.c lib_unctrl.c
|
|
lib_window.c panel.c
|
|
|
|
This module is pure curses, but calls outstr():
|
|
|
|
lib_getstr.c
|
|
|
|
These modules are pure curses, except that they use tputs() and
|
|
putp():
|
|
|
|
lib_beep.c lib_color.c lib_endwin.c lib_options.c lib_slk.c
|
|
lib_vidattr.c
|
|
|
|
This modules assist in POSIX emulation on non-POSIX systems:
|
|
|
|
sigaction.c
|
|
signal calls
|
|
|
|
The following source files will not be needed for a
|
|
single-terminal-type port.
|
|
|
|
alloc_entry.c captoinfo.c clear.c comp_captab.c comp_error.c
|
|
comp_hash.c comp_main.c comp_parse.c comp_scan.c dump_entry.c
|
|
infocmp.c parse_entry.c read_entry.c tput.c write_entry.c
|
|
|
|
The following modules will use open()/read()/write()/close()/lseek()
|
|
on files, but no other OS calls.
|
|
|
|
lib_screen.c
|
|
used to read/write screen dumps
|
|
|
|
lib_trace.c
|
|
used to write trace data to the logfile
|
|
|
|
Modules that would have to be modified for a port start here:
|
|
|
|
The following modules are `pure curses' but contain assumptions
|
|
inappropriate for a memory-mapped port.
|
|
|
|
lib_longname.c
|
|
assumes there may be multiple terminals
|
|
|
|
lib_acs.c
|
|
assumes acs_map as a double indirection
|
|
|
|
lib_mvcur.c
|
|
assumes cursor moves have variable cost
|
|
|
|
lib_termcap.c
|
|
assumes there may be multiple terminals
|
|
|
|
lib_ti.c
|
|
assumes there may be multiple terminals
|
|
|
|
The following modules use UNIX-specific calls:
|
|
|
|
lib_doupdate.c
|
|
input checking
|
|
|
|
lib_getch.c
|
|
read()
|
|
|
|
lib_initscr.c
|
|
getenv()
|
|
|
|
lib_newterm.c
|
|
lib_baudrate.c
|
|
lib_kernel.c
|
|
various tty-manipulation and system calls
|
|
|
|
lib_raw.c
|
|
various tty-manipulation calls
|
|
|
|
lib_setup.c
|
|
various tty-manipulation calls
|
|
|
|
lib_restart.c
|
|
various tty-manipulation calls
|
|
|
|
lib_tstp.c
|
|
signal-manipulation calls
|
|
|
|
lib_twait.c
|
|
gettimeofday(), select().
|
|
_________________________________________________________________
|
|
|
|
|
|
Eric S. Raymond <esr@snark.thyrsus.com>
|
|
|
|
(Note: This is not the bug address!)
|