--- name: "luit" section: "1x" platform: "linux" package: "xutils" version: "4.3.0.dfsg.1-14sarge7" release: "Debian 3.1 (Sarge)" platforms: ["linux"] url: "https://new.carta.tech/luit/1x" --- # luit(1x) Locale and ISO 2022 support for Unicode terminals ## NAME luit - Locale and ISO 2022 support for Unicode terminals ## SYNOPSIS **luit** \[ *options* \] \[ **--** \] \[ *program* \[ *args* \] \] ## DESCRIPTION **Luit** is a filter that can be run between an arbitrary application and a UTF-8 terminal emulator. It will convert application output from the locale's encoding into UTF-8, and convert terminal input from UTF-8 into the locale's encoding. An application may also request switching to a different output encoding using ISO 2022 and ISO 6429 escape sequences. Use of this feature is discouraged: multilingual applications should be modified to directly generate UTF-8 instead. **Luit** is usually invoked transparently by the terminal emulator. For information about running **luit** from the command line, see EXAMPLES below. ## OPTIONS - **-h** Display some summary help and quit. - **-list** List the supported charsets and encodings, then quit. - **-v** Be verbose. - **-c** Function as a simple converter from standard input to standard output. - **-x** Exit as soon as the child dies. This may cause **luit** to loose data at the end of the child's output. - **-argv0** *name* Set the child's name (as passed in argv\[0\]). - **-encoding** *encoding* Set up **luit** to use *encoding* rather than the current locale's encoding. - **+oss** Disable interpretation of single shifts in application output. - **+ols** Disable interpretation of locking shifts in application output. - **+osl** Disable interpretation of character set selection sequences in application output. - **+ot** Disable interpretation of all sequences and pass all sequences in application output to the terminal unchanged. This may lead to interesting results. - **-k7** Generate seven-bit characters for keyboard input. - **+kss** Disable generation of single-shifts for keyboard input. - **+kssgr** Use GL codes after a single shift for keyboard input. By default, GR codes are generated after a single shift when generating eight-bit keyboard input. - **-kls** Generate locking shifts (SO/SI) for keyboard input. - **-gl** *gn* Set the initial assignment of GL. The argument should be one of **g0**, **g1**, **g2** or **g3**. The default depends on the locale, but is usually **g0**. - **-gr** *gk* Set the initial assignment of GR. The default depends on the locale, and is usually **g2** except for EUC locales, where it is **g1**. - **-g0** *charset* Set the charset initially selected in G0. The default depends on the locale, but is usually **ASCII**. - **-g1** *charset* Set the charset initially selected in G1. The default depends on the locale. - **-g2** *charset* Set the charset initially selected in G2. The default depends on the locale. - **-g3** *charset* Set the charset initially selected in G3. The default depends on the locale. - **-ilog** *filename* Log into *filename* all the bytes received from the child. - **-olog** *filename* Log into *filename* all the bytes sent to the terminal emulator. - **--** End of options. ## EXAMPLES The most typical use of **luit** is to adapt an instance of **XTerm** to the locale's encoding. Current versions of **XTerm** invoke **luit** automatically when it is needed. If you are using an older release of **XTerm**, or a different terminal emulator, you may invoke **luit** manually: - $ xterm -u8 -e luit If you are running in a UTF-8 locale but need to access a remote machine that doesn't support UTF-8, **luit** can adapt the remote output to your terminal: - $ LC\_ALL=fr\_FR luit ssh legacy-machine **Luit** is also useful with applications that hard-wire an encoding that is different from the one normally used on the system or want to use legacy escape sequences for multilingual output. In particular, versions of **Emacs** that do not speak UTF-8 well can use **luit** for multilingual output: - $ luit -encoding 'ISO 8859-1' emacs -nw And then, in **Emacs**, - M-x set-terminal-coding-system RET iso-2022-8bit-ss2 RET ## FILES - **/usr/X11R6/lib/X11/fonts/encodings/encodings.dir** The system-wide encodings directory. - **/usr/X11R6/lib/X11/locale/locale.alias** The file mapping locales to locale encodings. ## SECURITY On systems with SVR4 (\`\`Unix-98'') ptys (Linux version 2.2 and later, SVR4), **luit** should be run as the invoking user. On systems without SVR4 (\`\`Unix-98'') ptys (notably BSD variants), running **luit** as an ordinary user will leave the tty world-writable; this is a security hole, and luit will generate a warning (but still accept to run). A possible solution is to make **luit** suid root; **luit** should drop privileges sufficiently early to make this safe. However, the startup code has not been exhaustively audited, and the author takes no responsibility for any resulting security issues. **Luit** will refuse to run if it is installed setuid and the underlying system does not have POSIX saved ids. ## BUGS None of this complexity should be necessary. Stateless UTF-8 throughout the system is the way to go. Charsets with a non-trivial intermediary byte are not yet supported. Selecting alternate sets of control characters is not supported and will never be. ## SEE ALSO [xterm(1)](/xterm/1.md), [unicode(7)](/unicode/7.md), [utf-8(7)](/utf-8/7.md), [charsets(7)](/charsets/7.md). *Character Code Structure and Extension Techniques (ISO 2022, ECMA-35).* *Control Functions for Coded Character Sets (ISO 6429, ECMA-48).* ## AUTHOR Luit was written by Juliusz Chroboczek \ for the XFree86 project.