This is Info file ./termcap.info, produced by Makeinfo-1.55 from the input file ./termcap.texi. This file documents the termcap library of the GNU system. Copyright (C) 1988 Free Software Foundation, Inc. Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Permission is granted to copy and distribute translations of this manual into another language, under the above conditions for modified versions, except that this permission notice may be stated in a translation approved by the Foundation.  File: termcap.info, Node: Insdel Char, Next: Standout, Prev: Insdel Line, Up: Capabilities Insert/Delete Character ======================= "Inserting a character" means creating a blank space in the middle of a line, and pushing the rest of the line rightward. The character in the rightmost column is lost. "Deleting a character" means causing the character to disappear from the screen, closing up the gap by moving the rest of the line leftward. A blank space appears in the rightmost column. Insertion and deletion of characters is useful in programs that maintain an updating display some parts of which may get longer or shorter. It is also useful in editors for redisplaying the results of editing within a line. Many terminals provide commands to insert or delete a single character at the cursor position. Some provide the ability to insert or delete several characters with one command, using the number of characters to insert or delete as a parameter. Many terminals provide an insert mode in which outputting a graphic character has the added effect of inserting a position for that character. A special command string is used to enter insert mode and another is used to exit it. The reason for designing a terminal with an insert mode rather than an insert command is that inserting character positions is usually followed by writing characters into them. With insert mode, this is as fast as simply writing the characters, except for the fixed overhead of entering and leaving insert mode. However, when the line speed is great enough, padding may be required for the graphic characters output in insert mode. Some terminals require you to enter insert mode and then output a special command for each position to be inserted. Or they may require special commands to be output before or after each graphic character to be inserted. Deletion of characters is usually accomplished by a straightforward command to delete one or several positions; but on some terminals, it is necessary to enter a special delete mode before using the delete command, and leave delete mode afterward. Sometimes delete mode and insert mode are the same mode. Some terminals make a distinction between character positions in which a space character has been output and positions which have been cleared. On these terminals, the effect of insert or delete character runs to the first cleared position rather than to the end of the line. In fact, the effect may run to more than one line if there is no cleared position to stop the shift on the first line. These terminals are identified by the `in' flag capability. On terminals with the `in' flag, the technique of skipping over characters that you know were cleared, and then outputting text later on in the same line, causes later insert and delete character operations on that line to do nonstandard things. A program that has any chance of doing this must check for the `in' flag and must be careful to write explicit space characters into the intermediate columns when `in' is present. A plethora of terminal capabilities are needed to describe all of this complexity. Here is a list of them all. Following the list, we present an algorithm for programs to use to take proper account of all of these capabilities. `im' String of commands to enter insert mode. If the terminal has no special insert mode, but it can insert characters with a special command, `im' should be defined with a null value, because the `vi' editor assumes that insertion of a character is impossible if `im' is not provided. New programs should not act like `vi'. They should pay attention to `im' only if it is defined. `ei' String of commands to leave insert mode. This capability must be present if `im' is. On a few old terminals the same string is used to enter and exit insert mode. This string turns insert mode on if it was off, and off it it was on. You can tell these terminals because the `ei' string equals the `im' string. If you want to support these terminals, you must always remember accurately whether insert mode is in effect. However, these terminals are obsolete, and it is reasonable to refuse to support them. On all modern terminals, you can safely output `ei' at any time to ensure that insert mode is turned off. `ic' String of commands to insert one character position at the cursor. The cursor does not move. If outputting a graphic character while in insert mode is sufficient to insert the character, then the `ic' capability should be defined with a null value. If your terminal offers a choice of ways to insert--either use insert mode or use a special command--then define `im' and do not define `ic', since this gives the most efficient operation when several characters are to be inserted. *Do not* define both strings, for that means that *both* must be used each time insertion is done. `ip' String of commands to output following an inserted graphic character in insert mode. Often it is used just for a padding spec, when padding is needed after an inserted character (*note Padding::.). `IC' String of commands to insert N character positions at and after the cursor. It has the same effect as repeating the `ic' string and a space, N times. If `IC' is provided, application programs may use it without first entering insert mode. `mi' Flag whose presence means it is safe to move the cursor while in insert mode and assume the terminal remains in insert mode. `in' Flag whose presence means that the terminal distinguishes between character positions in which space characters have been output and positions which have been cleared. An application program can assume that the terminal can do character insertion if *any one of* the capabilities `IC', `im', `ic' or `ip' is provided. To insert N blank character positions, move the cursor to the place to insert them and follow this algorithm: 1. If an `IC' string is provided, output it with parameter N and you are finished. Otherwise (or if you don't want to bother to look for an `IC' string) follow the remaining steps. 2. Output the `im' string, if there is one, unless the terminal is already in insert mode. 3. Repeat steps 4 through 6, N times. 4. Output the `ic' string if any. 5. Output a space. 6. Output the `ip' string if any. 7. Output the `ei' string, eventually, to exit insert mode. There is no need to do this right away. If the `mi' flag is present, you can move the cursor and the cursor will remain in insert mode; then you can do more insertion elsewhere without reentering insert mode. To insert N graphic characters, position the cursor and follow this algorithm: 1. If an `IC' string is provided, output it with parameter N, then output the graphic characters, and you are finished. Otherwise (or if you don't want to bother to look for an `IC' string) follow the remaining steps. 2. Output the `im' string, if there is one, unless the terminal is already in insert mode. 3. For each character to be output, repeat steps 4 through 6. 4. Output the `ic' string if any. 5. Output the next graphic character. 6. Output the `ip' string if any. 7. Output the `ei' string, eventually, to exit insert mode. There is no need to do this right away. If the `mi' flag is present, you can move the cursor and the cursor will remain in insert mode; then you can do more insertion elsewhere without reentering insert mode. Note that this is not the same as the original Unix termcap specifications in one respect: it assumes that the `IC' string can be used without entering insert mode. This is true as far as I know, and it allows you be able to avoid entering and leaving insert mode, and also to be able to avoid the inserted-character padding after the characters that go into the inserted positions. Deletion of characters is less complicated; deleting one column is done by outputting the `dc' string. However, there may be a delete mode that must be entered with `dm' in order to make `dc' work. `dc' String of commands to delete one character position at the cursor. If `dc' is not present, the terminal cannot delete characters. `DC' String of commands to delete N characters starting at the cursor. It has the same effect as repeating the `dc' string N times. Any terminal description that has `DC' also has `dc'. `dm' String of commands to enter delete mode. If not present, there is no delete mode, and `dc' can be used at any time (assuming there is a `dc'). `ed' String of commands to exit delete mode. This must be present if `dm' is. To delete N character positions, position the cursor and follow these steps: 1. If the `DC' string is present, output it with parameter N and you are finished. Otherwise, follow the remaining steps. 2. Output the `dm' string, unless you know the terminal is already in delete mode. 3. Output the `dc' string N times. 4. Output the `ed' string eventually. If the flag capability `mi' is present, you can move the cursor and do more deletion without leaving and reentering delete mode. As with the `IC' string, we have departed from the original termcap specifications by assuming that `DC' works without entering delete mode even though `dc' would not. If the `dm' and `im' capabilities are both present and have the same value, it means that the terminal has one mode for both insertion and deletion. It is useful for a program to know this, because then it can do insertions after deletions, or vice versa, without leaving insert/delete mode and reentering it.  File: termcap.info, Node: Standout, Next: Underlining, Prev: Insdel Char, Up: Capabilities Standout and Appearance Modes ============================= "Appearance modes" are modifications to the ways characters are displayed. Typical appearance modes include reverse video, dim, bright, blinking, underlined, invisible, and alternate character set. Each kind of terminal supports various among these, or perhaps none. For each type of terminal, one appearance mode or combination of them that looks good for highlighted text is chosen as the "standout mode". The capabilities `so' and `se' say how to enter and leave standout mode. Programs that use appearance modes only to highlight some text generally use the standout mode so that they can work on as many terminals as possible. Use of specific appearance modes other than "underlined" and "alternate character set" is rare. Terminals that implement appearance modes fall into two general classes as to how they do it. In some terminals, the presence or absence of any appearance mode is recorded separately for each character position. In these terminals, each graphic character written is given the appearance modes current at the time it is written, and keeps those modes until it is erased or overwritten. There are special commands to turn the appearance modes on or off for characters to be written in the future. In other terminals, the change of appearance modes is represented by a marker that belongs to a certain screen position but affects all following screen positions until the next marker. These markers are traditionally called "magic cookies". The same capabilities (`so', `se', `mb' and so on) for turning appearance modes on and off are used for both magic-cookie terminals and per-character terminals. On magic cookie terminals, these give the commands to write the magic cookies. On per-character terminals, they change the current modes that affect future output and erasure. Some simple applications can use these commands without knowing whether or not they work by means of cookies. However, a program that maintains and updates a display needs to know whether the terminal uses magic cookies, and exactly what their effect is. This information comes from the `sg' capability. The `sg' capability is a numeric capability whose presence indicates that the terminal uses magic cookies for appearance modes. Its value is the number of character positions that a magic cookie occupies. Usually the cookie occupies one or more character positions on the screen, and these character positions are displayed as blank, but in some terminals the cookie has zero width. The `sg' capability describes both the magic cookie to turn standout on and the cookie to turn it off. This makes the assumption that both kinds of cookie have the same width on the screen. If that is not true, the narrower cookie must be "widened" with spaces until it has the same width as the other. On some magic cookie terminals, each line always starts with normal display; in other words, the scope of a magic cookie never extends over more than one line. But on other terminals, one magic cookie affects all the lines below it unless explicitly canceled. Termcap does not define any way to distinguish these two ways magic cookies can work. To be safe, it is best to put a cookie at the beginning of each line. On some per-character terminals, standout mode or other appearance modes may be canceled by moving the cursor. On others, moving the cursor has no effect on the state of the appearance modes. The latter class of terminals are given the flag capability `ms' ("can move in standout"). All programs that might have occasion to move the cursor while appearance modes are turned on must check for this flag; if it is not present, they should reset appearance modes to normal before doing cursor motion. A program that has turned on only standout mode should use `se' to reset the standout mode to normal. A program that has turned on only alternate character set mode should use `ae' to return it to normal. If it is possible that any other appearance modes are turned on, use the `me' capability to return them to normal. Note that the commands to turn on one appearance mode, including `so' and `mb' ... `mr', if used while some other appearance modes are turned on, may combine the two modes on some terminals but may turn off the mode previously enabled on other terminals. This is because some terminals do not have a command to set or clear one appearance mode without changing the others. Programs should not attempt to use appearance modes in combination except with `sa', and when switching from one single mode to another should always turn off the previously enabled mode and then turn on the new desired mode. On some old terminals, the `so' and `se' commands may be the same command, which has the effect of turning standout on if it is off, or off it is on. It is therefore risky for a program to output extra `se' commands for good measure. Fortunately, all these terminals are obsolete. Programs that update displays in which standout-text may be replaced with non-standout text must check for the `xs' flag. In a per-character terminal, this flag says that the only way to remove standout once written is to clear that portion of the line with the `ce' string or something even more powerful (*note Clearing::.); just writing new characters at those screen positions will not change the modes in effect there. In a magic cookie terminal, `xs' says that the only way to remove a cookie is to clear a portion of the line that includes the cookie; writing a different cookie at the same position does not work. Such programs must also check for the `xt' flag, which means that the terminal is a Teleray 1061. On this terminal it is impossible to position the cursor at the front of a magic cookie, so the only two ways to remove a cookie are (1) to delete the line it is on or (2) to position the cursor at least one character before it (possibly on a previous line) and output the `se' string, which on these terminals finds and removes the next `so' magic cookie on the screen. (It may also be possible to remove a cookie which is not at the beginning of a line by clearing that line.) The `xt' capability also has implications for the use of tab characters, but in that regard it is obsolete (*Note Cursor Motion::). `so' String of commands to enter standout mode. `se' String of commands to leave standout mode. `sg' Numeric capability, the width on the screen of the magic cookie. This capability is absent in terminals that record appearance modes character by character. `ms' Flag whose presence means that it is safe to move the cursor while the appearance modes are not in the normal state. If this flag is absent, programs should always reset the appearance modes to normal before moving the cursor. `xs' Flag whose presence means that the only way to reset appearance modes already on the screen is to clear to end of line. On a per-character terminal, you must clear the area where the modes are set. On a magic cookie terminal, you must clear an area containing the cookie. See the discussion above. `xt' Flag whose presence means that the cursor cannot be positioned right in front of a magic cookie, and that `se' is a command to delete the next magic cookie following the cursor. See discussion above. `mb' String of commands to enter blinking mode. `md' String of commands to enter double-bright mode. `mh' String of commands to enter half-bright mode. `mk' String of commands to enter invisible mode. `mp' String of commands to enter protected mode. `mr' String of commands to enter reverse-video mode. `me' String of commands to turn off all appearance modes, including standout mode and underline mode. On some terminals it also turns off alternate character set mode; on others, it may not. This capability must be present if any of `mb' ... `mr' is present. `as' String of commands to turn on alternate character set mode. This mode assigns some or all graphic characters an alternate picture on the screen. There is no standard as to what the alternate pictures look like. `ae' String of commands to turn off alternate character set mode. `sa' String of commands to turn on an arbitrary combination of appearance modes. It accepts 9 parameters, each of which controls a particular kind of appearance mode. A parameter should be 1 to turn its appearance mode on, or zero to turn that mode off. Most terminals do not support the `sa' capability, even among those that do have various appearance modes. The nine parameters are, in order, STANDOUT, UNDERLINE, REVERSE, BLINK, HALF-BRIGHT, DOUBLE-BRIGHT, BLANK, PROTECT, ALT CHAR SET.  File: termcap.info, Node: Underlining, Next: Cursor Visibility, Prev: Standout, Up: Capabilities Underlining =========== Underlining on most terminals is a kind of appearance mode, much like standout mode. Therefore, it may be implemented using magic cookies or as a flag in the terminal whose current state affects each character that is output. *Note Standout::, for a full explanation. The `ug' capability is a numeric capability whose presence indicates that the terminal uses magic cookies for underlining. Its value is the number of character positions that a magic cookie for underlining occupies; it is used for underlining just as `sg' is used for standout. Aside from the simplest applications, it is impossible to use underlining correctly without paying attention to the value of `ug'. `us' String of commands to turn on underline mode or to output a magic cookie to start underlining. `ue' String of commands to turn off underline mode or to output a magic cookie to stop underlining. `ug' Width of magic cookie that represents a change of underline mode; or missing, if the terminal does not use a magic cookie for this. `ms' Flag whose presence means that it is safe to move the cursor while the appearance modes are not in the normal state. Underlining is an appearance mode. If this flag is absent, programs should always turn off underlining before moving the cursor. There are two other, older ways of doing underlining: there can be a command to underline a single character, or the output of `_', the ASCII underscore character, as an overstrike could cause a character to be underlined. New programs need not bother to handle these capabilities unless the author cares strongly about the obscure terminals which support them. However, terminal descriptions should provide these capabilities when appropriate. `uc' String of commands to underline the character under the cursor, and move the cursor right. `ul' Flag whose presence means that the terminal can underline by overstriking an underscore character (`_'); some terminals can do this even though they do not support overstriking in general. An implication of this flag is that when outputting new text to overwrite old text, underscore characters must be treated specially lest they underline the old text instead.  File: termcap.info, Node: Cursor Visibility, Next: Bell, Prev: Underlining, Up: Capabilities Cursor Visibility ================= Some terminals have the ability to make the cursor invisible, or to enhance it. Enhancing the cursor is often done by programs that plan to use the cursor to indicate to the user a position of interest that may be anywhere on the screen--for example, the Emacs editor enhances the cursor on entry. Such programs should always restore the cursor to normal on exit. `vs' String of commands to enhance the cursor. `vi' String of commands to make the cursor invisible. `ve' String of commands to return the cursor to normal. If you define either `vs' or `vi', you must also define `ve'.  File: termcap.info, Node: Bell, Next: Keypad, Prev: Cursor Visibility, Up: Capabilities Bell ==== Here we describe commands to make the terminal ask for the user to pay attention to it. `bl' String of commands to cause the terminal to make an audible sound. If this capability is absent, the terminal has no way to make a suitable sound. `vb' String of commands to cause the screen to flash to attract attention ("visible bell"). If this capability is absent, the terminal has no way to do such a thing.  File: termcap.info, Node: Keypad, Next: Meta Key, Prev: Bell, Up: Capabilities Keypad and Function Keys ======================== Many terminals have arrow and function keys that transmit specific character sequences to the computer. Since the precise sequences used depend on the terminal, termcap defines capabilities used to say what the sequences are. Unlike most termcap string-valued capabilities, these are not strings of commands to be sent to the terminal, rather strings that are received from the terminal. Programs that expect to use keypad keys should check, initially, for a `ks' capability and send it, to make the keypad actually transmit. Such programs should also send the `ke' string when exiting. `ks' String of commands to make the keypad keys transmit. If this capability is not provided, but the others in this section are, programs may assume that the keypad keys always transmit. `ke' String of commands to make the keypad keys work locally. This capability is provided only if `ks' is. `kl' String of input characters sent by typing the left-arrow key. If this capability is missing, you cannot expect the terminal to have a left-arrow key that transmits anything to the computer. `kr' String of input characters sent by typing the right-arrow key. `ku' String of input characters sent by typing the up-arrow key. `kd' String of input characters sent by typing the down-arrow key. `kh' String of input characters sent by typing the "home-position" key. `K1' ... `K5' Strings of input characters sent by the five other keys in a 3-by-3 array that includes the arrow keys, if the keyboard has such a 3-by-3 array. Note that one of these keys may be the "home-position" key, in which case one of these capabilities will have the same value as the `kh' key. `k0' String of input characters sent by function key 10 (or 0, if the terminal has one labeled 0). `k1' ... `k9' Strings of input characters sent by function keys 1 through 9, provided for those function keys that exist. `kn' Number: the number of numbered function keys, if there are more than 10. `l0' ... `l9' Strings which are the labels appearing on the keyboard on the keys described by the capabilities `k0' ... `l9'. These capabilities should be left undefined if the labels are `f0' or `f10' and `f1' ... `f9'. `kH' String of input characters sent by the "home down" key, if there is one. `kb' String of input characters sent by the "backspace" key, if there is one. `ka' String of input characters sent by the "clear all tabs" key, if there is one. `kt' String of input characters sent by the "clear tab stop this column" key, if there is one. `kC' String of input characters sent by the "clear screen" key, if there is one. `kD' String of input characters sent by the "delete character" key, if there is one. `kL' String of input characters sent by the "delete line" key, if there is one. `kM' String of input characters sent by the "exit insert mode" key, if there is one. `kE' String of input characters sent by the "clear to end of line" key, if there is one. `kS' String of input characters sent by the "clear to end of screen" key, if there is one. `kI' String of input characters sent by the "insert character" or "enter insert mode" key, if there is one. `kA' String of input characters sent by the "insert line" key, if there is one. `kN' String of input characters sent by the "next page" key, if there is one. `kP' String of input characters sent by the "previous page" key, if there is one. `kF' String of input characters sent by the "scroll forward" key, if there is one. `kR' String of input characters sent by the "scroll reverse" key, if there is one. `kT' String of input characters sent by the "set tab stop in this column" key, if there is one. `ko' String listing the other function keys the terminal has. This is a very obsolete way of describing the same information found in the `kH' ... `kT' keys. The string contains a list of two-character termcap capability names, separated by commas. The meaning is that for each capability name listed, the terminal has a key which sends the string which is the value of that capability. For example, the value `:ko=cl,ll,sf,sr:' says that the terminal has four function keys which mean "clear screen", "home down", "scroll forward" and "scroll reverse".  File: termcap.info, Node: Meta Key, Next: Initialization, Prev: Keypad, Up: Capabilities Meta Key ======== A Meta key is a key on the keyboard that modifies each character you type by controlling the 0200 bit. This bit is on if and only if the Meta key is held down when the character is typed. Characters typed using the Meta key are called Meta characters. Emacs uses Meta characters as editing commands. `km' Flag whose presence means that the terminal has a Meta key. `mm' String of commands to enable the functioning of the Meta key. `mo' String of commands to disable the functioning of the Meta key. If the terminal has `km' but does not have `mm' and `mo', it means that the Meta key always functions. If it has `mm' and `mo', it means that the Meta key can be turned on or off. Send the `mm' string to turn it on, and the `mo' string to turn it off. I do not know why one would ever not want it to be on.  File: termcap.info, Node: Initialization, Next: Pad Specs, Prev: Meta Key, Up: Capabilities Initialization ============== `ti' String of commands to put the terminal into whatever special modes are needed or appropriate for programs that move the cursor nonsequentially around the screen. Programs that use termcap to do full-screen display should output this string when they start up. `te' String of commands to undo what is done by the `ti' string. Programs that output the `ti' string on entry should output this string when they exit. `is' String of commands to initialize the terminal for each login session. `if' String which is the name of a file containing the string of commands to initialize the terminal for each session of use. Normally `is' and `if' are not both used. `i1' `i3' Two more strings of commands to initialize the terminal for each login session. The `i1' string (if defined) is output before `is' or `if', and the `i3' string (if defined) is output after. The reason for having three separate initialization strings is to make it easier to define a group of related terminal types with slightly different initializations. Define two or three of the strings in the basic type; then the other types can override one or two of the strings. `rs' String of commands to reset the terminal from any strange mode it may be in. Normally this includes the `is' string (or other commands with the same effects) and more. What would go in the `rs' string but not in the `is' string are annoying or slow commands to bring the terminal back from strange modes that nobody would normally use. `it' Numeric value, the initial spacing between hardware tab stop columns when the terminal is powered up. Programs to initialize the terminal can use this to decide whether there is a need to set the tab stops. If the initial width is 8, well and good; if it is not 8, then the tab stops should be set; if they cannot be set, the kernel is told to convert tabs to spaces, and other programs will observe this and do likewise. `ct' String of commands to clear all tab stops. `st' String of commands to set tab stop at current cursor column on all lines. `NF' Flag whose presence means that the terminal does not support XON/XOFF flow control. Programs should not send XON (`C-q') or XOFF (`C-s') characters to the terminal.  File: termcap.info, Node: Pad Specs, Next: Status Line, Prev: Initialization, Up: Capabilities Padding Capabilities ==================== There are two terminal capabilities that exist just to explain the proper way to obey the padding specifications in all the command string capabilities. One, `pc', must be obeyed by all termcap-using programs. `pb' Numeric value, the lowest baud rate at which padding is actually needed. Programs may check this and refrain from doing any padding at lower speeds. `pc' String of commands for padding. The first character of this string is to be used as the pad character, instead of using null characters for padding. If `pc' is not provided, use null characters. Every program that uses termcap must look up this capability and use it to set the variable `PC' that is used by `tputs'. *Note Padding::. Some termcap capabilities exist just to specify the amount of padding that the kernel should give to cursor motion commands used in ordinary sequential output. `dC' Numeric value, the number of msec of padding needed for the carriage-return character. `dN' Numeric value, the number of msec of padding needed for the newline (linefeed) character. `dB' Numeric value, the number of msec of padding needed for the backspace character. `dF' Numeric value, the number of msec of padding needed for the formfeed character. `dT' Numeric value, the number of msec of padding needed for the tab character. In some systems, the kernel uses the above capabilities; in other systems, the kernel uses the paddings specified in the string capabilities `cr', `sf', `le', `ff' and `ta'. Descriptions of terminals which require such padding should contain the `dC' ... `dT' capabilities and also specify the appropriate padding in the corresponding string capabilities. Since no modern terminals require padding for ordinary sequential output, you probably won't need to do either of these things.  File: termcap.info, Node: Status Line, Next: Half-Line, Prev: Pad Specs, Up: Capabilities Status Line =========== A "status line" is a line on the terminal that is not used for ordinary display output but instead used for a special message. The intended use is for a continuously updated description of what the user's program is doing, and that is where the name "status line" comes from, but in fact it could be used for anything. The distinguishing characteristic of a status line is that ordinary output to the terminal does not affect it; it changes only if the special status line commands of this section are used. `hs' Flag whose presence means that the terminal has a status line. If a terminal description specifies that there is a status line, it must provide the `ts' and `fs' capabilities. `ts' String of commands to move the terminal cursor into the status line. Usually these commands must specifically record the old cursor position for the sake of the `fs' string. `fs' String of commands to move the cursor back from the status line to its previous position (outside the status line). `es' Flag whose presence means that other display commands work while writing the status line. In other words, one can clear parts of it, insert or delete characters, move the cursor within it using `ch' if there is a `ch' capability, enter and leave standout mode, and so on. `ds' String of commands to disable the display of the status line. This may be absent, if there is no way to disable the status line display. `ws' Numeric value, the width of the status line. If this capability is absent in a terminal that has a status line, it means the status line is the same width as the other lines. Note that the value of `ws' is sometimes as small as 8.  File: termcap.info, Node: Half-Line, Next: Printer, Prev: Status Line, Up: Capabilities Half-Line Motion ================ Some terminals have commands for moving the cursor vertically by half-lines, useful for outputting subscripts and superscripts. Mostly it is hardcopy terminals that have such features. `hu' String of commands to move the cursor up half a line. If the terminal is a display, it is your responsibility to avoid moving up past the top line; however, most likely the terminal that supports this is a hardcopy terminal and there is nothing to be concerned about. `hd' String of commands to move the cursor down half a line. If the terminal is a display, it is your responsibility to avoid moving down past the bottom line, etc.  File: termcap.info, Node: Printer, Prev: Half-Line, Up: Capabilities Controlling Printers Attached to Terminals ========================================== Some terminals have attached hardcopy printer ports. They may be able to copy the screen contents to the printer; they may also be able to redirect output to the printer. Termcap does not have anything to tell the program whether the redirected output appears also on the screen; it does on some terminals but not all. `ps' String of commands to cause the contents of the screen to be printed. If it is absent, the screen contents cannot be printed. `po' String of commands to redirect further output to the printer. `pf' String of commands to terminate redirection of output to the printer. This capability must be present in the description if `po' is. `pO' String of commands to redirect output to the printer for next N characters of output, regardless of what they are. Redirection will end automatically after N characters of further output. Until then, nothing that is output can end redirection, not even the `pf' string if there is one. The number N should not be more than 255. One use of this capability is to send non-text byte sequences (such as bit-maps) to the printer. Most terminals with printers do not support all of `ps', `po' and `pO'; any one or two of them may be supported. To make a program that can send output to all kinds of printers, it is necessary to check for all three of these capabilities, choose the most convenient of the ones that are provided, and use it in its own appropriate fashion.  File: termcap.info, Node: Summary, Next: Var Index, Prev: Capabilities, Up: Top Summary of Capability Names *************************** Here are all the terminal capability names in alphabetical order with a brief description of each. For cross references to their definitions, see the index of capability names (*note Cap Index::.). `ae' String to turn off alternate character set mode. `al' String to insert a blank line before the cursor. `AL' String to insert N blank lines before the cursor. `am' Flag: output to last column wraps cursor to next line. `as' String to turn on alternate character set mode.like. `bc' Very obsolete alternative name for the `le' capability. `bl' String to sound the bell. `bs' Obsolete flag: ASCII backspace may be used for leftward motion. `bt' String to move the cursor left to the previous hardware tab stop column. `bw' Flag: `le' at left margin wraps to end of previous line. `CC' String to change terminal's command character. `cd' String to clear the line the cursor is on, and following lines. `ce' String to clear from the cursor to the end of the line. `ch' String to position the cursor at column C in the same line. `cl' String to clear the entire screen and put cursor at upper left corner. `cm' String to position the cursor at line L, column C. `CM' String to position the cursor at line L, column C, relative to display memory. `co' Number: width of the screen. `cr' String to move cursor sideways to left margin. `cs' String to set the scroll region. `cS' Alternate form of string to set the scroll region. `ct' String to clear all tab stops. `cv' String to position the cursor at line L in the same column. `da' Flag: data scrolled off top of screen may be scrolled back. `db' Flag: data scrolled off bottom of screen may be scrolled back. `dB' Obsolete number: msec of padding needed for the backspace character. `dc' String to delete one character position at the cursor. `dC' Obsolete number: msec of padding needed for the carriage-return character. `DC' String to delete N characters starting at the cursor. `dF' Obsolete number: msec of padding needed for the formfeed character. `dl' String to delete the line the cursor is on. `DL' String to delete N lines starting with the cursor's line. `dm' String to enter delete mode. `dN' Obsolete number: msec of padding needed for the newline character. `do' String to move the cursor vertically down one line. `DO' String to move cursor vertically down N lines. `ds' String to disable the display of the status line. `dT' Obsolete number: msec of padding needed for the tab character. `ec' String of commands to clear N characters at cursor. `ed' String to exit delete mode. `ei' String to leave insert mode. `eo' Flag: output of a space can erase an overstrike. `es' Flag: other display commands work while writing the status line. `ff' String to advance to the next page, for a hardcopy terminal. `fs' String to move the cursor back from the status line to its previous position (outside the status line). `gn' Flag: this terminal type is generic, not real. `hc' Flag: hardcopy terminal. `hd' String to move the cursor down half a line. `ho' String to position cursor at upper left corner. `hs' Flag: the terminal has a status line. `hu' String to move the cursor up half a line. `hz' Flag: terminal cannot accept `~' as output. `i1' String to initialize the terminal for each login session. `i3' String to initialize the terminal for each login session. `ic' String to insert one character position at the cursor. `IC' String to insert N character positions at the cursor. `if' String naming a file of commands to initialize the terminal. `im' String to enter insert mode. `in' Flag: outputting a space is different from moving over empty positions. `ip' String to output following an inserted character in insert mode. `is' String to initialize the terminal for each login session. `it' Number: initial spacing between hardware tab stop columns. `k0' String of input sent by function key 0 or 10. `k1 ... k9' Strings of input sent by function keys 1 through 9. `K1 ... K5' Strings sent by the five other keys in 3-by-3 array with arrows. `ka' String of input sent by the "clear all tabs" key. `kA' String of input sent by the "insert line" key. `kb' String of input sent by the "backspace" key. `kC' String of input sent by the "clear screen" key. `kd' String of input sent by typing the down-arrow key. `kD' String of input sent by the "delete character" key. `ke' String to make the function keys work locally. `kE' String of input sent by the "clear to end of line" key. `kF' String of input sent by the "scroll forward" key. `kh' String of input sent by typing the "home-position" key. `kH' String of input sent by the "home down" key. `kI' String of input sent by the "insert character" or "enter insert mode" key. `kl' String of input sent by typing the left-arrow key. `kL' String of input sent by the "delete line" key. `km' Flag: the terminal has a Meta key. `kM' String of input sent by the "exit insert mode" key. `kn' Numeric value, the number of numbered function keys. `kN' String of input sent by the "next page" key. `ko' Very obsolete string listing the terminal's named function keys. `kP' String of input sent by the "previous page" key. `kr' String of input sent by typing the right-arrow key. `kR' String of input sent by the "scroll reverse" key. `ks' String to make the function keys transmit. `kS' String of input sent by the "clear to end of screen" key. `kt' String of input sent by the "clear tab stop this column" key. `kT' String of input sent by the "set tab stop in this column" key. `ku' String of input sent by typing the up-arrow key. `l0' String on keyboard labelling function key 0 or 10. `l1 ... l9' Strings on keyboard labelling function keys 1 through 9. `le' String to move the cursor left one column. `LE' String to move cursor left N columns. `li' Number: height of the screen. `ll' String to position cursor at lower left corner. `lm' Number: lines of display memory. `LP' Flag: writing to last column of last line will not scroll. `mb' String to enter blinking mode. `md' String to enter double-bright mode. `me' String to turn off all appearance modes `mh' String to enter half-bright mode. `mi' Flag: cursor motion in insert mode is safe. `mk' String to enter invisible mode. `mm' String to enable the functioning of the Meta key. `mo' String to disable the functioning of the Meta key. `mp' String to enter protected mode. `mr' String to enter reverse-video mode. `ms' Flag: cursor motion in standout mode is safe. `nc' Obsolete flag: do not use ASCII carriage-return on this terminal. `nd' String to move the cursor right one column. `NF' Flag: do not use XON/XOFF flow control. `nl' Obsolete alternative name for the `do' and `sf' capabilities. `ns' Flag: the terminal does not normally scroll for sequential output. `nw' String to move to start of next line, possibly clearing rest of old line. `os' Flag: terminal can overstrike. `pb' Number: the lowest baud rate at which padding is actually needed. `pc' String containing character for padding. `pf' String to terminate redirection of output to the printer. `po' String to redirect further output to the printer. `pO' String to redirect N characters ofoutput to the printer. `ps' String to print the screen on the attached printer. `rc' String to move to last saved cursor position. `RI' String to move cursor right N columns. `rp' String to output character C repeated N times. `rs' String to reset the terminal from any strange modes. `sa' String to turn on an arbitrary combination of appearance modes. `sc' String to save the current cursor position. `se' String to leave standout mode. `sf' String to scroll the screen one line up. `SF' String to scroll the screen N lines up. `sg' Number: width of magic standout cookie. Absent if magic cookies are not used. `so' String to enter standout mode. `sr' String to scroll the screen one line down. `SR' String to scroll the screen N line down. `st' String to set tab stop at current cursor column on all lines. programs. `ta' String to move the cursor right to the next hardware tab stop column. `te' String to return terminal to settings for sequential output. `ti' String to initialize terminal for random cursor motion. `ts' String to move the terminal cursor into the status line. `uc' String to underline one character and move cursor right. `ue' String to turn off underline mode `ug' Number: width of underlining magic cookie. Absent if underlining doesn't use magic cookies. `ul' Flag: underline by overstriking with an underscore. `up' String to move the cursor vertically up one line. `UP' String to move cursor vertically up N lines. `us' String to turn on underline mode `vb' String to make the screen flash. `ve' String to return the cursor to normal. `vi' String to make the cursor invisible. `vs' String to enhance the cursor. `wi' String to set the terminal output screen window. `ws' Number: the width of the status line. `xb' Flag: superbee terminal. `xn' Flag: cursor wraps in a strange way. `xs' Flag: clearing a line is the only way to clear the appearance modes of positions in that line (or, only way to remove magic cookies on that line). `xt' Flag: Teleray 1061; several strange characteristics.  File: termcap.info, Node: Var Index, Next: Cap Index, Prev: Summary, Up: Top Variable and Function Index *************************** * Menu: * BC: tgoto. * ospeed: Output Padding. * PC: Output Padding. * tgetent: Find. * tgetflag: Interrogate. * tgetnum: Interrogate. * tgetstr: Interrogate. * tgoto: tgoto. * tparam: tparam. * tputs: Output Padding. * UP: tgoto.