mirror of https://github.com/tLDP/LDP
updated
This commit is contained in:
parent
568ebb577c
commit
6ee92be993
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@ -2358,7 +2358,7 @@ implementation, plus auxiliary packages like Ghostscript. </Para>
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Text-Terminal-HOWTO</ULink>,
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<CiteTitle>Text-Terminal HOWTO</CiteTitle>
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</Para><Para>
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<CiteTitle>Updated: October 2001</CiteTitle>.
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<CiteTitle>Updated: November 2001</CiteTitle>.
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Explains what text terminals are, how they work, how to install and
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configure them, and provides some info on how to repair them. </Para>
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</ListItem>
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|
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@ -263,7 +263,7 @@ a Psion palmtop. </Para>
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Text-Terminal-HOWTO</ULink>,
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<CiteTitle>Text-Terminal HOWTO</CiteTitle>
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</Para><Para>
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<CiteTitle>Updated: October 2001</CiteTitle>.
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<CiteTitle>Updated: November 2001</CiteTitle>.
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Explains what text terminals are, how they work, how to install and
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configure them, and provides some info on how to repair them. </Para>
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</ListItem>
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|
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@ -2,10 +2,12 @@
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<article>
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<title> Text-Terminal-HOWTO
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<author> David S. Lawyer <url url="mailto:dave@lafn.org">
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<date> v1.25, Oct. 2001
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<date> v1.26, November 2001
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<!--
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Change log:
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v1.26 Nov. 2001: text browsers, fixed link to cca.org (was caa.org),
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about 20 typos fixed
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v1.25 Oct. 2001: Linux Terminal Server Project, bad line in inittab
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may cause respawning too rapidly, Evolution of the "terminal server"
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had contents in title (my format error), elminating overstrikes in
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|
@ -142,7 +144,8 @@ Up A Terminal Connected To My PC?" was incorporated into v1.00 at
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various places. v1.09 has about 25 changes (and error corrections)
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suggested by Alessandro Rubini who reviewed this HOWTO. Jeremy Jon
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Spykerman told me about using a keyboardless terminal as a console for
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a monitorless PC (using ttysnoop).
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a monitorless PC (using ttysnoop). In 2001 (v1.26) I fixed about 25
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typos, etc. found by Alain Cochard:
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<sect1> Future Plans: You Can Help
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<p> Please let me know of any errors in facts, opinions, logic,
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@ -173,22 +176,27 @@ url="http://linuxdoc.org/mirrors.html">. Various formats are
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available. If you only want to quickly check the date of the latest
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||||
version look at <url
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url="http://linuxdoc.org/HOWTO/Text-Terminal-HOWTO.html">. The
|
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version your are currently reading is: v1.25, Oct. 2001 . New in recent
|
||||
versions:<newline>
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v1.25 Oct. 2001: Linux Terminal Server Project, bad line in inittab
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may cause respawning too rapidly, Evolution of the "terminal server"
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had contents in title (my format error), elminating overstrikes in
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files
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v1.24 Aug. 2001 Respawning too fast due to no such device, block mode
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obsolete, troubleshooting: displays escape sequences, detective work
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for repair
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v1.23 July 2001: 10-cond. is not RJ45/48 ?, corrupted character attributes
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v1.22 May 2001 Clarity: 8-bit, ASCII, national replacement characters,
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version your are currently reading is: v1.26, November 2001 . New in recent
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versions:
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<itemize>
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<item>v1.26 Nov. 2001: text browsers, fixed link to cca.org (was caa.org),
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about 20 typos fixed
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<item>v1.25 Oct. 2001: Linux Terminal Server Project, bad line in inittab
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may cause respawning too rapidly, Evolution of the "terminal server"
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had contents in title (my format error), elminating overstrikes in
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files
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<item>v1.24 Aug. 2001 Respawning too fast due to no such device, block mode
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obsolete, troubleshooting: displays escape sequences, detective work
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for repair
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<item>v1.23 July 2001: 10-cond. is not RJ45/48 ?, corrupted character attributes
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<item>v1.22 May 2001 Clarity: 8-bit, ASCII, national replacement characters,
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CP1252=MS-ANSI
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v1.21 April 2001 More on mgetty, getty-login sequence, agetty parity
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<item>v1.21 April 2001 More on mgetty, getty-login sequence, agetty parity
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problem, types of "terminal servers", parity set shows upper 128
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chars., Correction: PCTerm doesn't work with MS DOS, troubleshooting:
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no CD signal
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</itemize>
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<sect1> Related HOWTOs, etc. <label id="related_howtos">
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<p> Go to the nearest mirror site (per above) to get HOWTOs.
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|
@ -239,11 +247,11 @@ etc. A cable connected the terminal to the computer (often
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indirectly). It was called a terminal since it was located at the
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terminal end of this cable.
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If you've been using Linux (except for X-Window use) with a computer
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If you've been using Linux (except for X Window use) with a computer
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monitor and keyboard you already know what a terminal is because you
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have been using one (or more precisely a "virtual terminal"). The
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monitor (along with the keyboard) is emulating a terminal. In
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X-Windows the programs xterm, rxvt, and zterm emulate terminals.
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X Window the programs xterm, rxvt, and zterm emulate terminals.
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A real terminal is different from a monitor because it's a different
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electronic setup. A text terminal is often connected to a serial port
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@ -349,7 +357,7 @@ They use smart electronics to draw lines and curves with an electron
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beam that can move in any direction (at any angle and location). True
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vector graphics draws high quality lines without zig-zags but is both
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rare and expensive. For more details see <url
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url="http://www.caa.org/vector/">. Raster graphics is almost
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url="http://www.cca.org/vector/">. Raster graphics is almost
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universally used today for both PCs and text terminals. For PCs,
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images encoded in vector graphic format are sometimes used but they
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are translated to raster graphics format for display (with a resulting
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|
@ -403,8 +411,8 @@ server running Windows. They are also called "Window-based Terminals"
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claim to be WBTs (even though they can be used as WBTs). They are
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something like computers since they run an operating system (often
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stored in flash memory so it may be updated). Some can support
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X-Windows also and can be used for Linux (from a Linux server). Many
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so called "network computers" can also run X-Windows. This will be
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X Window also and can be used for Linux (from a Linux server). Many
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so called "network computers" can also run X Window. This will be
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discussed in the next section.
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For displaying the MS-Windows GUI, Citrix was (and is) a major player
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@ -436,7 +444,7 @@ server computer. They are a little different from terminals since
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some of the programs they run may execute on their own CPU chips.
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Running a browser was supposed to be one of their primary functions
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and thus Java code applets may be sent to them for execution. Many
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NCs support X-Windows so that one may use a Linux server to support
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NCs support X Window so that one may use a Linux server to support
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it. Such a server may be called a "Linux Terminal Server". IBM
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called their NC a "NetStation" but now calls it "NetVista". They
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should work on Intranet type networks and NetVista can run the the
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@ -468,7 +476,7 @@ computer can run programs on another computer. Such a program sends
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messages over the network so that it appears just like a program was
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being run by your local computer. But such a program is actually
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being run on another computer on the network. It works also with
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X-Windows so that one may see GUI images generated on another
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X Window so that one may see GUI images generated on another
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computer.
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Linux also allows a computer to be diskless and boot over a network.
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@ -496,9 +504,9 @@ starts up it sends a message to the Linux Server asking for the
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non-linux OS files. This non-linux OS is thus sent to the NC over the
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network and the NC boots.
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The Linux Server runs the NFS and X-Windows both of which must be
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The Linux Server runs the NFS and X Window both of which must be
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supported by the NC. This enables one to use the NC as if it were an
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X-Window terminal.
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X Window terminal.
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There are some Linux HOWTOs for certain brands of NCs:
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@ -639,7 +647,7 @@ computer.
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For a fair comparison with PC's, the terminals should have the same
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capabilities as the PC monitors. Unfortunately, color graphic
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terminals for Linux (X-windows) with high speed communication is a
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terminals for Linux (X Window) with high speed communication is a
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niche market with high prices so in this case there is not likely to
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be any savings in hardware costs. But for text terminals there will
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be some savings, especially if the terminals are obtained used at low
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@ -721,7 +729,7 @@ Files"> for details on these and related "devices" such as cua.
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<sect1> Login/Logout
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<p> When the host computer starts up it runs the program getty. The
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getty program runs the "login" program to log people in. See <ref
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id="getty_" name="Getty (in /etc/inittab)">. A "login:" prompt
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id="getty_" name="Getty (used in /etc/inittab)">. A "login:" prompt
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appears on the screen. People at the terminals log in (after giving
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their passwords) and then have access to the computer. When it's time
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to shut the terminal down, one normally logs out and turns the
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@ -857,9 +865,9 @@ otherwise get detected.
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The most common type of emulation is to use a PC like it was a vt100
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terminal (or the like). Programs loaded into the PC's memory do the
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emulation. In Linux (unless you're in X-windows) the PC monitor
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emulation. In Linux (unless you're in X Window) the PC monitor
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(called the console) emulates a terminal of type "Linux" (close to
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vt100). Even certain windows within X-windows emulate terminals. See
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vt100). Even certain windows within X Window emulate terminals. See
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<ref id="term_emulation" name="Terminal Emulation">.
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<sect1> The Console
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@ -927,7 +935,7 @@ For example, if someone connects via telnet to your computer over a
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network, they may wind up connected to the device /dev/ptyp2 (a pseudo
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terminal port). The login process logs them in to /dev/ttyp2. Here
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the login program and the telnet program talk to each other via a
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"pseudo terminal". In X-Windows, the terminal emulator program, xterm
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"pseudo terminal". In X Window, the terminal emulator program, xterm
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(or rxvt), uses pseudo terminals. Ham radio programs under Linux also
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use them. Using certain application software it is possible to have 2
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or more pseudo terminals attached to the same physical serial port.
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@ -944,7 +952,7 @@ like) which supplies (and gets) data to/from the slave port.
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Unix98 doesn't use the above but instead uses a "pty master" which is
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/dev/ptmx. This can supply a pty on demand. While other unix-like
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systems have a manual page for pseudo terminals (may be named "pty")
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Linux lacks one. page devoted to only to pseudo terminals is needed
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Linux lacks one. A page devoted to only to pseudo terminals is needed
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for Linux. There is both a Linux pty module and a /usr/include/pty.h
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file.
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@ -968,11 +976,12 @@ emulate modems and may be given modem commands.
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<p> In Linux the PC monitor is usually called the console and has
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several device special files associated with it: tty0, tty1, tty2,
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etc. When you log in you are on tty1. To go to tty2 (on the same
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screen) For tty3 use Left Alt-F3, etc. These (tty1, tty2, tty3, etc.)
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||||
are called "virtual terminals". tty0 is just an alias for the current
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virtual terminal and it's where messages from the system are sent.
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Thus messages from the system will be seen on the console (monitor)
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regardless of which virtual terminal it is displaying.
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screen) press down the 2 keys Alt(left)-F3. For tty3 use Left Alt-F3,
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etc. These (tty1, tty2, tty3, etc.) are called "virtual terminals".
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tty0 is just an alias for the current virtual terminal and it's where
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messages from the system are sent. Thus messages from the system will
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be seen on the console (monitor) regardless of which virtual terminal
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it is displaying.
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You may log in to different virtual terminals and thus have a few
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different sessions with the computer going on at the same time. Only
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|
@ -1093,7 +1102,7 @@ usually there.
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<sect1> Display Attributes & Magic Cookies <label id="display_attributes">
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<p> Terminals have various methods of generating character attributes
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such as bold, reverse-video, underlining, etc. There should be
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no need for the user to worry about how how this is done, except that
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no need for the user to worry about how this is done, except that
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it creates problems for some old terminals and there is sometimes an
|
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option for this in the set-up menu of newer terminals.
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|
@ -1168,7 +1177,7 @@ print job (text only) to your terminal to be printed on a printer
|
|||
attached to the terminal. It's homepage is <tt><htmlurl
|
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url="http://www.yavin.org/software/vtprint/"> </tt>. It's also
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included (as of 1998) in the Debian distribution of Linux. <tt/xprt/
|
||||
(also in Debian) seems to do something similar, but only for X-Window
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(also in Debian) seems to do something similar, but only for X Window
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terminals ??
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|
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<sect1> Pages <label id="pages_">
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||||
|
@ -1433,7 +1442,8 @@ capabilities (including a choice of colors). Sometimes the emulation
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|||
is not 100% perfect but this usually causes few problems. For using a
|
||||
Mac computer to emulate a terminal see the mini-howto: Mac-Terminal.
|
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|
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<sect1> Don't Use TERM For Emulation <label id="term_not_for_emulation">
|
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<sect1> Don't Use TERM Variable For Emulation
|
||||
<label id="term_not_for_emulation">
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||||
<p> Some have erroneously thought that they could create an emulator
|
||||
at a Linux console (monitor) by setting the environment variable TERM
|
||||
to the type of terminal they would like to emulate. This does not
|
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|
@ -1458,7 +1468,7 @@ normally include any terminal emulation. But some other modem dialing
|
|||
programs (such as minicom or seyon) do. Using them one may (for
|
||||
example) dial up public libraries to use their catalogs and indexes,
|
||||
(or even read magazine articles). They are also useful for testing
|
||||
modems. Seyon is only for use with X-windows and can emulate
|
||||
modems. Seyon is only for use with X Window and can emulate
|
||||
Tektronix 4014 terminals.
|
||||
|
||||
The communication program Kermit doesn't do terminal emulation as it
|
||||
|
@ -1475,8 +1485,8 @@ Emulators exist under DOS such as <tt/telix/ and <tt/procomm/ work
|
|||
just as well. The terminal emulated is often the old VT100, VT102, or
|
||||
ANSI (like VT100).
|
||||
|
||||
<sect2> Emulation under X-Windows
|
||||
<p> Xterm (obsolete ??) may be run under X-Windows which can emulate a
|
||||
<sect2> Emulation under X Window
|
||||
<p> Xterm (obsolete ??) may be run under X Window which can emulate a
|
||||
VT102, VT220, or Tektronix 4014. There is also an xterm emulation
|
||||
(although there is no physical terminal named "xterm"). If you don't
|
||||
need the Tektronix 4014 emulation (a vector graphics terminal; see
|
||||
|
@ -1491,7 +1501,7 @@ has a built-in editor and scroll-bars. It was designed for Plan 9, a
|
|||
Unix-like operating system from AT&T.
|
||||
|
||||
<sect2> Real terminals better
|
||||
<p> Unless you are using X-Windows with a large display, a real
|
||||
<p> Unless you are using X Window with a large display, a real
|
||||
terminal is often nicer to use than emulating one. It usually costs
|
||||
less, has better resolution for text, and has no disk drives to make
|
||||
annoying noises.
|
||||
|
@ -1558,9 +1568,13 @@ software you should try to throughly check out what you will get.
|
|||
<p> Unless you want to emulate the standard vt100 (or close to it).
|
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There doesn't seem to be much free terminal emulation software
|
||||
available for Linux. The free programs minicom and seyon (only for
|
||||
X-windows) can emulate a vt100 (or close to it). Seyon can also
|
||||
X Window) can emulate a vt100 (or close to it). Seyon can also
|
||||
emulate a Tektronix 4014 terminal.
|
||||
|
||||
The terminal emulator "Procomm" (which is from Dos), can be used on a
|
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Linux PC if you run dosemu to emulate Dos. For details see: <url
|
||||
url="http://solarflow.dyndns.org/pcplus">.
|
||||
|
||||
There's a specialized Linux distribution: Serial Terminal Linux. It
|
||||
will turn a PC to into a minicom-like terminal. It's small (fits on a
|
||||
floppy) and will not let you use the PC for any other purpose (when
|
||||
|
@ -2550,7 +2564,7 @@ only have one or two connectors to install.
|
|||
<sect1> Intro to Set-Up
|
||||
<p> Configuring (Set-Up) involves both storing a configuration in the
|
||||
non-volatile memory of the terminal, and putting commands in start-up
|
||||
files (on you hard disk) that will run each time the computer is
|
||||
files (on your hard disk) that will run each time the computer is
|
||||
powered on (or possibly only when the run-level changes). This
|
||||
section gives an overview of configuring and covers the configuring of
|
||||
the essential communication options for both the terminal and the
|
||||
|
@ -2571,7 +2585,7 @@ There are two basic ways of configuring a terminal. One is to sit at
|
|||
the terminal and go thru a series of set-up menus. Another is to send
|
||||
escape sequences to it from the host computer. Before you can send
|
||||
anything to the terminal (such as the above escape sequences), its
|
||||
<ref id="commun_config" name="Communication Interface">) options such
|
||||
<ref id="commun_config" name="Communication Interface"> options such
|
||||
as the baud rate must be set up to match those of the computer. This
|
||||
can only be done by sitting at the terminal since the communications
|
||||
must be set up right before the computer and the terminal can "talk"
|
||||
|
@ -2581,21 +2595,21 @@ Set-Up">.
|
|||
<sect1> Computer Set-Up (Configure) Overview
|
||||
<p> Besides possibly sending escape sequences from the computer to
|
||||
configure the terminal, there is the configuring of the computer
|
||||
itself to handle the terminal. If your lucky, all you need to do is to
|
||||
put a "getty" command in the /etc/inittab file so that a "login:" prompt
|
||||
will be sent to the terminal when the computer starts up. See <ref
|
||||
id="getty_" name="Getty (in /etc/inittab)"> for details.
|
||||
this for the computer.
|
||||
itself to handle the terminal. If your'e lucky, all you need to do is
|
||||
to put a "getty" command in the /etc/inittab file so that a "login:"
|
||||
prompt will be sent to the terminal when the computer starts up. See
|
||||
the section <ref id="getty_" name="Getty (used in /etc/inittab)"> for
|
||||
details.
|
||||
|
||||
The computer communicates with the terminal using the device driver
|
||||
software (part of the kernel). The serial device driver has a default
|
||||
configuration and is also partly (sometimes fully) configured by the
|
||||
getty program before running "login" at each terminal. However,
|
||||
additional configuration is sometimes needed using programs named "stty"
|
||||
and "setserial". These programs (if needed) must be run each time the
|
||||
computer starts up since this configuration is lost each time the
|
||||
computer powers down. See <ref id="comp_conf_details" name="Computer
|
||||
Set-Up (Configure) Details">.
|
||||
The computer communicates with the terminal using the serial device
|
||||
driver software (part of the kernel). The serial device driver has a
|
||||
default configuration and is also partly (sometimes fully) configured
|
||||
by the getty program before running "login" at each terminal.
|
||||
However, additional configuration is sometimes needed using programs
|
||||
named "stty" and "setserial". These programs (if needed) must be run
|
||||
each time the computer starts up since this configuration is lost each
|
||||
time the computer powers down. See <ref id="comp_conf_details"
|
||||
name="Computer Set-Up (Configure) Details">.
|
||||
|
||||
<sect1> Many Options
|
||||
<p> There are a great many configuration options for you to choose
|
||||
|
@ -2605,7 +2619,7 @@ problem since the features they set may not be used. For example, if
|
|||
you don't have a printer connected to the terminal it makes no
|
||||
difference how the printer configuration parameters are set inside the
|
||||
terminal. This last statement is not 100% correct. Suppose that you
|
||||
have no printer but the compute (by mistake) sends the terminal a
|
||||
have no printer but the computer (by mistake) sends the terminal a
|
||||
command to redirect all characters (data) from the computer to the
|
||||
printer only. Then nothing will display on the screen and your
|
||||
terminal will be dead. Some terminals have a configuration option to
|
||||
|
@ -2644,7 +2658,7 @@ of special cartridge at each terminal). The host computer is
|
|||
configured by running commands each time the computer is powered up
|
||||
(or when people log in). Sometimes the getty program (found in the
|
||||
/etc/inittab file) which starts the login process will take care of
|
||||
this for the computer. See <ref id="getty_" name="Getty (in
|
||||
this for the computer. See <ref id="getty_" name="Getty (used in
|
||||
/etc/inittab)">
|
||||
|
||||
The settings for both the computer and the terminal are:
|
||||
|
@ -2661,10 +2675,10 @@ Some essential settings for the terminal alone are:
|
|||
<item> Set communication to full duplex (=FDX on Wyse terminals)
|
||||
</itemize>
|
||||
|
||||
If the <ref id="getty_" name="Getty (in /etc/inittab)"> program can't
|
||||
set up the computer side the way you want, then you may need to use
|
||||
one (or both) of the <ref id="stty_setserial" name="Stty & Setserial">
|
||||
commands.
|
||||
If the <ref id="getty_" name="Getty (used in /etc/inittab)"> program
|
||||
can't set up the computer side the way you want, then you may need to
|
||||
use one (or both) of the <ref id="stty_setserial" name="Stty &
|
||||
Setserial"> commands.
|
||||
|
||||
<sect2> Speed <label id="speed">
|
||||
<p> These must be set the same on both the terminal and the computer.
|
||||
|
@ -2786,11 +2800,11 @@ many of the options which you might possibly need to set.
|
|||
The communication parameters such as its baud rate must always be set
|
||||
up at the terminal since if this is not done there can be no
|
||||
communication with the terminal. Once communication is established
|
||||
you have two choices for doing the rest the terminal configuration.
|
||||
you have two choices for doing the rest of the terminal configuration.
|
||||
You may continue to configure manually at the terminal and save the
|
||||
results in the terminal's non-volatile memory or you may do
|
||||
this by sending escape sequences to the terminal from the computer
|
||||
each time the terminal is powered on (or the like).
|
||||
results in the terminal's non-volatile memory or you may do this by
|
||||
sending escape sequences to the terminal from the computer each time
|
||||
the terminal is powered on (or the like).
|
||||
|
||||
If you know how to set up and save a good configuration inside the
|
||||
terminal it may be the best way. If you don't, you might want to just
|
||||
|
@ -3318,8 +3332,8 @@ something important programmed into the function keys.
|
|||
|
||||
<sect1> Screen Saver {Scrn Saver}
|
||||
<p> Also called "CRT Saver". This turns off (or dims) the screen
|
||||
after the terminal is not used for a period of time. It prolongs the
|
||||
life of the screen and may save some energy. Hitting any key will
|
||||
after the terminal is not used for a period of time. It may prolong
|
||||
the life of the screen and save some energy. Hitting any key will
|
||||
usually restore the screen and may "execute" that key so it's best to
|
||||
hit the shift-key, etc.
|
||||
|
||||
|
@ -3341,7 +3355,7 @@ job? If {Print Term} is set to FF, this will happen.
|
|||
terminals. If you're lucky, you'll only need to edit /etc/inittab.
|
||||
One does this by editing at the console (or from any working terminal).
|
||||
|
||||
<sect1> Getty (in /etc/inittab) <label id="getty_">
|
||||
<sect1> Getty (used in /etc/inittab) <label id="getty_">
|
||||
<sect2> Introduction to Getty
|
||||
<p> In order to have a login process run on a serial port (and the
|
||||
terminal connected to it) when the computer starts up (or switches run
|
||||
|
@ -3406,9 +3420,10 @@ The format of this depends on which getty you use.
|
|||
This is the sequence of events that happens after getty starts up.
|
||||
<sect2> Getty "exits" after login (and can respawn).
|
||||
-->
|
||||
<p>After you log in you will notice (by using "top" or "ps -ax") that
|
||||
the getty process is no longer running. What happened to it? Why
|
||||
does getty restart again if your shell is killed? Here's why.
|
||||
<p>After you log in you will notice (by using "top", "ps -ax", or
|
||||
"ptree") that the getty process is no longer running. What happened
|
||||
to it? Why does getty restart again if your shell is killed? Here's
|
||||
why.
|
||||
|
||||
After you type in your user name, getty takes it and calls the login
|
||||
program telling it your user name. The getty process is replaced
|
||||
|
@ -3488,7 +3503,7 @@ command line after editing getty and you should see a login prompt.
|
|||
<p> The <tt/agetty/ program will attempt to auto-detect the parity set
|
||||
inside the terminal (including no parity). It doesn't support 8-bit
|
||||
data bytes plus 1-bit parity. See <ref id="parity_8-bit" name="8-bit
|
||||
data bytes (plus parity)"> If you use <tt/stty/ to set parity,
|
||||
data bytes (plus parity)">. If you use <tt/stty/ to set parity,
|
||||
<tt/agetty/ will automatically unset it since it initially wants the
|
||||
parity bit to come thru as if it was a data bit. This is because it
|
||||
needs to get the last bit (possibly a parity bit) as you type your
|
||||
|
@ -3674,12 +3689,12 @@ are some minor differences, depending on which HOWTO it appears in.
|
|||
read <ref id="laptops_" name="Laptops: PCMCIA">. <tt/setserial/ is a
|
||||
program which allows you to tell the device driver software the I/O
|
||||
address of the serial port, which interrupt (IRQ) is set in the port's
|
||||
hardware, what type of UART you have, etc. Since theres a good chance
|
||||
that the serial ports will be automatically detected and set, many
|
||||
people never need to use <tt/setserial/. In any case setserial will
|
||||
not work without either serial support built into the kernel or loaded
|
||||
as a module. The module may get loaded automatically if you (or a
|
||||
script) tries to use setserial.
|
||||
hardware, what type of UART you have, etc. Since there's a good
|
||||
chance that the serial ports will be automatically detected and set,
|
||||
many people never need to use <tt/setserial/. In any case setserial
|
||||
will not work without either serial support built into the kernel or
|
||||
loaded as a module. The module may get loaded automatically if you
|
||||
(or a script) tries to use setserial.
|
||||
|
||||
Setserial can also show how the driver is currently set. In addition,
|
||||
it can be made to probe the hardware I0 port addresses to try to
|
||||
|
@ -4018,11 +4033,11 @@ configuration. For serial ports on the motherboard, setserial is used
|
|||
just like it is for a desktop. But for PCMCIA cards (such as a modem)
|
||||
it's a different story. The configuring of the PCMCIA system should
|
||||
automatically run setserial so you shouldn't need to run it. If you
|
||||
you do run it (by a script file or by /etc/serial.conf) it might
|
||||
be different and cause trouble. The autosave feature for serial.conf
|
||||
shouldn't save anything for PCMCIA cards (but Debian did until 2.15-7).
|
||||
Of course, it's always OK to use setserial to find out how the driver
|
||||
is configured for PCMCIA cards.
|
||||
do run it (by a script file or by /etc/serial.conf) it might be
|
||||
different and cause trouble. The autosave feature for serial.conf
|
||||
shouldn't save anything for PCMCIA cards (but Debian did until
|
||||
2.15-7). Of course, it's always OK to use setserial to find out how
|
||||
the driver is configured for PCMCIA cards.
|
||||
|
||||
<!-- setserial.H end -->
|
||||
|
||||
|
@ -4032,7 +4047,7 @@ In Serial and Text-Terminal -->
|
|||
<sect2> Introduction
|
||||
<p> <tt/stty/ does much of the configuration of the serial port but
|
||||
since application programs (and the getty program) often handle it,
|
||||
you may not need to use it much. It's handy if your having problems
|
||||
you may not need to use it much. It's handy if you're having problems
|
||||
or want to see how the port is set up. Try typing ``stty -a'' at your
|
||||
terminal/console to see how it's now set. Also try typing it without
|
||||
the -a (all) for a short listing which shows how it's set different
|
||||
|
@ -4058,13 +4073,15 @@ tasks to write to terminal?, define special (control) characters (such
|
|||
as what key to press for interrupt). See the <tt/stty/ man or info
|
||||
page for more details. Also see the man page: <tt/termios/ which
|
||||
covers the same options set by stty but (as of mid 1999) covers
|
||||
features which the stty man page fails to mention.
|
||||
features which the stty man page fails to mention.
|
||||
For use of some special characters see <ref
|
||||
id="stty_chars" name="Special (Control) Characters">
|
||||
|
||||
With some implementations of getty (getty_ps package), the commands
|
||||
that one would normally give to stty are typed into a getty
|
||||
configuration file: /etc/gettydefs. Even without this configuration
|
||||
file, the getty command line may be sufficient to set things up so
|
||||
that you don't need stty."')
|
||||
that you don't need stty.
|
||||
|
||||
One may write C programs which change the stty configuration, etc.
|
||||
Looking at some of the documentation for this may help one better
|
||||
|
@ -4446,7 +4463,7 @@ would help avoid this problem.
|
|||
there's another way to get the source-code if you have the compiled
|
||||
code. Just use the "<tt/infocmp/" command.
|
||||
|
||||
The source code file (for all terminals0 may be /etc/termcap and/or
|
||||
The source code file (for all terminals) may be /etc/termcap and/or
|
||||
terminfo.src (or another name). See the man pages: terminfo(5) or
|
||||
termcap(5) for the format required to create (or modify) these source
|
||||
files. The file terminfo.src may be in various locations on your
|
||||
|
@ -4479,7 +4496,7 @@ the terminfo database.
|
|||
<p> In order to save disk space, one may delete all of the terminfo
|
||||
database except for the terminals types that you have (or might need
|
||||
in the future). Don't delete any of the termcaps for a "Linux
|
||||
terminal" (the console) or the xterm ones if you use X-Windows. The
|
||||
terminal" (the console) or the xterm ones if you use X Window. The
|
||||
terminal type "dumb" may be needed when an application program can't
|
||||
figure out what type of terminal you are using. It would save disk
|
||||
space if install programs only installed the terminfo for the
|
||||
|
@ -4585,7 +4602,7 @@ yes or types in the actual terminal type s/he is using. Then tset
|
|||
sends the init string and sets TERM to this terminal name (type).
|
||||
|
||||
<sect1> Terminfo/Termcap Documents <label id="termcap_docs">
|
||||
<p> <itemize> <item>
|
||||
<p> <itemize>
|
||||
<item> manual pages for terminfo(5) (best) and/or termcap(5).
|
||||
<url url="http://www.delorie.com/gnu/docs/termcap/termcap_toc.html"
|
||||
name="The Termcap Manual"> (2nd ed.) by Richard M. Stallman is a GNU
|
||||
|
@ -4825,7 +4842,7 @@ likely to corrupt things if you: "cat ...." or "cp .... /dev/tty.." or
|
|||
run a program which sends binary output to "standard output" (unless
|
||||
you redirect such output with >, etc.).
|
||||
|
||||
Corruption it can also happen when using a communications program where
|
||||
Corruption can also happen when using a communications program where
|
||||
a remote computer may send binary to your screen. There are numerous
|
||||
other ways it can happen so be prepared for it. Even a supposedly
|
||||
text file could contain unwanted control codes.
|
||||
|
@ -4858,7 +4875,7 @@ bug report in Mar. 2000 but never got a "fixed" notice.
|
|||
the normal ones, pressing ^O may switch back to the normal letters.
|
||||
The "reset" command also does this but it resets everything else too.
|
||||
|
||||
There"s the case where all letters have the wrong attribute (too dim,
|
||||
There's the case where all letters have the wrong attribute (too dim,
|
||||
bright, blinking, or even invisible :-) but the whitespace created by
|
||||
tab characters is normal. This was caused by an escape sequence which
|
||||
set this attribute but the attribute doesn't apply to the whitespace
|
||||
|
@ -5162,6 +5179,17 @@ be different depending on whether a shell is running on it, whether
|
|||
it's at the "login" prompt, etc. Thus the stty configuration after
|
||||
switching runlevels may vary.
|
||||
|
||||
<sect1>Browsers for Terminals
|
||||
<p>The "lynx" browser works fine with terminals. There are two other
|
||||
text browsers: "w3m" and "links" that only work correctly with the
|
||||
Linux console or vt100 terminals.
|
||||
|
||||
"w3m" and "links" overcomes some of the "lynx" deficiencies. They can
|
||||
display tables better and can display frames side-by-side (but they
|
||||
may appear cramped). Unfortunately, they don't have numbered links
|
||||
like lynx does nor do they have good support for cookies. None of
|
||||
these 3 text browsers support Java script.
|
||||
|
||||
<sect> Special Uses for a Terminal
|
||||
<sect1>Make a Serial Terminal the Console <label id="term_as_console">
|
||||
|
||||
|
@ -5577,12 +5605,13 @@ garbled response) to your login attempts a possible cause is that the
|
|||
communication is bad one-way from the terminal to the computer. It
|
||||
could be a bad or mis-wired cable/connector. If you're not already
|
||||
using the "local" option with getty, do so to disable the modem
|
||||
control lines. See <ref id="getty_" name="Getty (in /etc/inittab)">.
|
||||
You might also disable hardware flow control (stty -crtscts) if it was
|
||||
enabled. If it now works OK then your modem control lines are likely
|
||||
either not wired correctly or there's a mistake in your set-up. Some
|
||||
terminals allow setting different values (such as baud rate) for send
|
||||
and receive so the receive could be OK but the send bad.
|
||||
control lines. See <ref id="getty_" name="Getty (used in
|
||||
/etc/inittab)">. You might also disable hardware flow control (stty
|
||||
-crtscts) if it was enabled. If it now works OK then your modem
|
||||
control lines are likely either not wired correctly or there's a
|
||||
mistake in your set-up. Some terminals allow setting different values
|
||||
(such as baud rate) for send and receive so the receive could be OK
|
||||
but the send bad.
|
||||
|
||||
You should also (at the console) try "stty < /dev/ttyS1" (if you use
|
||||
ttyS1) to see that it's set up correctly. It will often be in raw
|
||||
|
@ -6167,18 +6196,21 @@ effect.
|
|||
<p> If it's a stuck key on a keyboard with individual switches, a good
|
||||
way to fix it is to remove the keycap (if it's removable). See
|
||||
id="kbd_sw" name="Keyboards with individual switches">. Use a small
|
||||
amount of cleaner on the push rod. Some keys stick due to stickiness
|
||||
on the keycap bottom surface (and where it hits on the switch). If
|
||||
the key sticks in the fully down position this could be the problem.
|
||||
So clean this this area too.
|
||||
amount of cleaner on the push rod. Press repeatedly on the key
|
||||
until it works OK and displays its character on the screen.
|
||||
At first, the cleaner may cause the key to fail to display its
|
||||
character. Some keys stick due to stickiness on the keycap bottom
|
||||
surface.. If the key sticks in the fully down position this could be
|
||||
the problem. So you might need to clean this this area too.
|
||||
|
||||
Hitting the key a lot to exercise it may help, but the problem is
|
||||
likely to return. If you suspect the push rod is sticking you might
|
||||
try to type it while pushing sideways on it with a small screwdriver.
|
||||
You should push it sideways in one of the four directions and try
|
||||
different directions. What you are doing by this is attempting to
|
||||
force out a foreign particle that is rubbing on the side of the key's
|
||||
push-rod and making it stick. Again, the problem may return later.
|
||||
While the best method is to use cleaner as per above, just hitting the
|
||||
key a lot to exercise it may help, but the problem is likely to
|
||||
return. If you suspect the push rod is sticking you might try to type
|
||||
it while pushing sideways on it with a small screwdriver. You should
|
||||
push it sideways in one of the four directions and try different
|
||||
directions. What you are doing by this is attempting to force out a
|
||||
foreign particle that is rubbing on the side of the key's push-rod and
|
||||
making it stick. Again, the problem may return later.
|
||||
|
||||
To test the key, push it down very slowly and see if it sticks. Also
|
||||
push it sideways a little as you're pushing it down. If you hit it
|
||||
|
@ -6186,7 +6218,7 @@ fast or push it straight down, then you may not observe the
|
|||
stickiness.
|
||||
|
||||
<sect3> Key electrically shorted
|
||||
<p>If you suspect that a key is shorted out fix it by cleaning the
|
||||
<p>If you suspect that a key is shorted out, fix it by cleaning the
|
||||
contacts per <ref id="clean_keys" name="Cleaning Keyboard Contacts">.
|
||||
If this problem happens at the login prompt see <ref
|
||||
id="key_shorted_getty" name="Key shorted">.
|
||||
|
|
Loading…
Reference in New Issue