From ffccd5b2b05243e7976db80f90f453dccfae9886 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 15 Apr 2024 22:22:03 +0200 Subject: Adding upstream version 3:4.8.30. Signed-off-by: Daniel Baumann --- contrib/README.xterm | 109 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 109 insertions(+) create mode 100644 contrib/README.xterm (limited to 'contrib/README.xterm') diff --git a/contrib/README.xterm b/contrib/README.xterm new file mode 100644 index 0000000..b37ebad --- /dev/null +++ b/contrib/README.xterm @@ -0,0 +1,109 @@ + Solving keyboard related problems + with XTERM + and GNU Midnight Commander + (and other programs as well). + +Xterm brings a handful of problems with input keys and their translations. +Some of these problems include xterm's failure to make a difference between +shifted and not shifted function keys (many keyboards do not have more than +10 or 12 function keys, so it is useful to generate higher function keys (11 +- 20) by pressing Shift and function key - 10 (e.g. Shift+F3 is F13). Xterm +also doesn't send Alt+character and Meta+character as something other than +plain character. Also, home key does not work on most systems. And keypad +operator characters (+, -, /, *) send different sequences than normal +, -, +/, * (or sometimes do not send anything). + +Please note that if you want to use the Alt key on an XTerm, you have to +make sure you use: + +XTerm*eightBitInput: false + +Otherwise, you will just get accented keys. + +Fortunately this can be solved, since xterm is written on top of the +X Toolkit Intrinsics, which has a built-in feature of event translation +tables that can be specified using X resources. This doesn't apply to rxvt, +where the only solution to this problem would be patching rxvt's sources and +recompiling. So from now on, we are speaking only about xterm (and its +modifications, like color_xterm and ansi_xterm). + +Xterm brings two new Xt widgets (if you don't know what they are it doesn't +matter), vt100 and tek4014 (these are used for the terminal display in vt100 +and tektronics mode). The translation table is specified in +*vt100.translations and *tek4014.translations resources. +You can see a sample in xterm.ad file in this directory. + +If you want to install these translations, bear in mind that you have to +keep your terminfo and termcap in sync with these. So if you install +xterm.ad, you have to install xterm.ti and xterm.tcap (or do necessary +changes yourself). + +xterm.ad has to be loaded into the Xrm (X resource manager), either by xterm +itself or by xrdb utility. There are many places you may want to install it +to; the decision is yours. Preferably it should go to your personal +$HOME/.Xdefaults file (if you have any). This file is automatically loaded +using xrdb whenever you start the X server (it is done by startx and openwin +scripts). Another possibility is to put this into +$X11ROOT/lib/X11/app-defaults/XTerm or wherever your app-defaults file of +xterm is and whatever is its name (sometimes it will have to be XTerm-ansi, +XTerm-color etc.) Or you can put this anywhere and call + xrdb xterm.ad +from any script you run on X11 startup. + +xterm.ti (terminfo database source) is installed by running `tic xterm.ti'. +tic will compile it and place it into your TERMINFO directory. + +xterm.tcap is the xterm (and xterm-color) termcap entry. It is based on the +newest termcap database from http://www.ccil.org/~esr/ncurses.html, but +contains a bunch of changes to make all the above mentioned keys work. Even +if mc is compiled so that it uses terminfo, you need to install the termcap +entry so that other programs which use termcap will behave correctly. You +have to edit your /etc/termcap and replace xterm and xterm-color entries +with those from xterm.tcap. + +The xterm.ad translation table contains many items (some of them may be +unnecessary) but are included only to make it work on all different xterms +(xterm terminfo and termcap databases have different sequences for the same +keys in every different database, so xterm.ad works as a standard to make +xterm.ti and termcap happy). If you find that xterm works well even if you +delete some lines from the translations, feel free to do it. + +By default, Alt+character keys received by mc are generated in xterm.ad by +Alt modifier plus the key. On some systems, you may want to change this to +the Meta modifier (e.g. if the Alt modifier is missing). You do it by +replacing a letter s at the beginning of table lines with letter m. + +And what you might want to know, if you are going to change anything, is: +Each line looks like + modifierskeyname: string("something") \n\ +where modifiers can be: +a for alt +m for meta +c for control +button1 (2, 3) for mouse buttons. + + The string is generated whenever the named key is pressed while the +modifiers are in a state matching the specification. Naming a modifier +specifies that the modifier must be pressed. A ~ in front of a modifier +name specifies that the modifier must NOT be pressed. If the set of +modifiers is preceded by !, unmentioned modifiers must not be +pressed; otherwise their state is ignored. + +After you specify a name of the key (if you don't know a canonical +name of any key, see $X11ROOT/include/X11/keysymdef.h (keynames are the +names there without leading XK_). Then there can be any sequence of string +statements which send the string to the tty line, as if the user typed that +sequence of characters. If it has the form string(0xXX), where X's are +hexadecimal digits, then the ascii character of that value is sent rather +than 0xXX. + +This is a subset of all the translation table features. If you want a +complete reference, see xterm(1) and X Toolkit Intrinsics manual Appendix B. + +Please, if you find any problems or errors in this stuff, let me know by +e-mail to +mc-devel@lists.midnight-commander.org. + + + + -- cgit v1.2.3