--- rxvt-unicode/README.FAQ 2005/12/17 20:55:45 1.19 +++ rxvt-unicode/README.FAQ 2006/01/12 05:37:34 1.25 @@ -1,7 +1,114 @@ FREQUENTLY ASKED QUESTIONS + I don't like the new selection/popups/hotkeys/perl, how do I + change/disable it? + You can disable the perl extension completely by setting the + perl-ext-common resource to the empty string, which also keeps + rxvt-unicode from initialising perl, saving memory. + + If you only want to disable specific features, you first have to + identify which perl extension is responsible. For this, read the + section PREPACKAGED EXTENSIONS in the rxvtperl(3) manpage. For + example, to disable the selection-popup and option-popup, specify + this perl-ext-common resource: + + URxvt.perl-ext-common: default,-selection-popup,-option-popup + + This will keep the default extensions, but disable the two popup + extensions. Some extensions can also be configured, for example, + scrollback search mode is triggered by M-s. You can move it to any + other combination either by setting the searchable-scrollback + resource: + + URxvt.searchable-scrollback: CM-s + + Isn't rxvt supposed to be small? Don't all those features bloat? + I often get asked about this, and I think, no, they didn't cause + extra bloat. If you compare a minimal rxvt and a minimal urxvt, you + can see that the urxvt binary is larger (due to some encoding tables + always being compiled in), but it actually uses less memory (RSS) + after startup. Even with "--disable-everything", this comparison is + a bit unfair, as many features unique to urxvt (locale, encoding + conversion, iso14755 etc.) are already in use in this mode. + + text data bss drs rss filename + 98398 1664 24 15695 1824 rxvt --disable-everything + 188985 9048 66616 18222 1788 urxvt --disable-everything + + When you "--enable-everything" (which _is_ unfair, as this involves + xft and full locale/XIM support which are quite bloaty inside libX11 + and my libc), the two diverge, but not unreasnobaly so. + + text data bss drs rss filename + 163431 2152 24 20123 2060 rxvt --enable-everything + 1035683 49680 66648 29096 3680 urxvt --enable-everything + + The very large size of the text section is explained by the + east-asian encoding tables, which, if unused, take up disk space but + nothing else and can be compiled out unless you rely on X11 core + fonts that use those encodings. The BSS size comes from the 64k + emergency buffer that my c++ compiler allocates (but of course + doesn't use unless you are out of memory). Also, using an xft font + instead of a core font immediately adds a few megabytes of RSS. Xft + indeed is responsible for a lot of RSS even when not used. + + Of course, due to every character using two or four bytes instead of + one, a large scrollback buffer will ultimately make rxvt-unicode use + more memory. + + Compared to e.g. Eterm (5112k), aterm (3132k) and xterm (4680k), + this still fares rather well. And compared to some monsters like + gnome-terminal (21152k + extra 4204k in separate processes) or + konsole (22200k + extra 43180k in daemons that stay around after + exit, plus half a minute of startup time, including the hundreds of + warnings it spits out), it fares extremely well *g*. + + Why C++, isn't that unportable/bloated/uncool? + Is this a question? :) It comes up very often. The simple answer is: + I had to write it, and C++ allowed me to write and maintain it in a + fraction of the time and effort (which is a scarce resource for me). + Put even shorter: It simply wouldn't exist without C++. + + My personal stance on this is that C++ is less portable than C, but + in the case of rxvt-unicode this hardly matters, as its portability + limits are defined by things like X11, pseudo terminals, locale + support and unix domain sockets, which are all less portable than + C++ itself. + + Regarding the bloat, see the above question: It's easy to write + programs in C that use gobs of memory, an certainly possible to + write programs in C++ that don't. C++ also often comes with large + libraries, but this is not necessarily the case with GCC. Here is + what rxvt links against on my system with a minimal config: + + libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x00002aaaaabc3000) + libc.so.6 => /lib/libc.so.6 (0x00002aaaaadde000) + libdl.so.2 => /lib/libdl.so.2 (0x00002aaaab01d000) + /lib64/ld-linux-x86-64.so.2 (0x00002aaaaaaab000) + + And here is rxvt-unicode: + + libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x00002aaaaabc3000) + libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x00002aaaaada2000) + libc.so.6 => /lib/libc.so.6 (0x00002aaaaaeb0000) + libdl.so.2 => /lib/libdl.so.2 (0x00002aaaab0ee000) + /lib64/ld-linux-x86-64.so.2 (0x00002aaaaaaab000) + + No large bloated libraries (of course, none were linked in + statically), except maybe libX11 :) + + Does it support tabs, can I have a tabbed rxvt-unicode? + rxvt-unicode does not directly support tabs. It will work fine with + tabbing functionality of many window managers or similar tabbing + programs, and its embedding-features allow it to be embedded into + other programs, as witnessed by doc/rxvt-tabbed or the upcoming + "Gtk2::URxvt" perl module, which features a tabbed urxvt (murxvt) + terminal as an example embedding application. + How do I know which rxvt-unicode version I'm using? The version number is displayed with the usage (-h). Also the escape sequence "ESC [ 8 n" sets the window title to the version number. + When using the rxvtc client, the version displayed is that of the + daemon. I am using Debian GNU/Linux and have a problem... The Debian GNU/Linux package of rxvt-unicode in sarge contains large @@ -18,6 +125,49 @@ also a bug in the Debian version and it serves as a reminder for other users that might encounter the same issue. + I am maintaining rxvt-unicode for distribution/OS XXX, any + recommendation? + You should build one binary with the default options. configure now + enables most useful options, and the trend goes to making them + runtime-switchable, too, so there is usually no drawback to enbaling + them, except higher disk and possibly memory usage. The perl + interpreter should be enabled, as important functionality (menus, + selection, likely more in the future) depends on it. + + You should not overwrite the "perl-ext-common" snd "perl-ext" + resources system-wide (except maybe with "defaults"). This will + result in useful behaviour. If your distribution aims at low memory, + add an empty "perl-ext-common" resource to the app-defaults file. + This will keep the perl interpreter disabled until the user enables + it. + + If you can/want build more binaries, I recommend building a minimal + one with "--disable-everything" (very useful) and a maximal one with + "--enable-everything" (less useful, it will be very big due to a lot + of encodings built-in that increase download times and are rarely + used). + + I need to make it setuid/setgid to support utmp/ptys on my OS, is this + safe? + Likely not. While I honestly try to make it secure, and am probably + not bad at it, I think it is simply unreasonable to expect all of + freetype + fontconfig + xft + xlib + perl + ... + rxvt-unicode + itself to all be secure. Also, rxvt-unicode disables some options + when it detects that it runs setuid or setgid, which is not nice. + Besides, with the embedded perl interpreter the possibility for + security problems easily multiplies. + + Elevated privileges are only required for utmp and pty operations on + some systems (for example, GNU/Linux doesn't need any extra + privileges for ptys, but some need it for utmp support). It is + planned to mvoe this into a forked handler process, but this is not + yet done. + + So, while setuid/setgid operation is supported and not a problem on + your typical single-user-no-other-logins unix desktop, always + remember that its an awful lot of code, most of which isn't checked + for security issues regularly. + When I log-in to another system it tells me about missing terminfo data? The terminal description used by rxvt-unicode is not as widely available as that for xterm, or even rxvt (for which the same