1.\" Copyright (c) 1985, 1991, 1993, 1994 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)termcap.5 8.3 (Berkeley) 4/16/94 33.\" $Id$ 34.\" 35.Dd April 16, 1994 36.Dt TERMCAP 5 37.Os BSD 3 38.Sh NAME 39.Nm termcap 40.Nd terminal capability data base 41.Sh SYNOPSIS 42.Nm termcap 43.Sh DESCRIPTION 44The 45.Nm Termcap 46file 47is a data base describing terminals, 48used, 49for example, 50by 51.Xr \&vi 1 52and 53.Xr curses 3 . 54Terminals are described in 55.Nm termcap 56by giving a set of capabilities that they have and by describing 57how operations are performed. 58Padding requirements and initialization sequences 59are included in 60.Nm termcap . 61.Pp 62Entries in 63.Nm termcap 64consist of a number of `:'-separated fields. 65The first entry for each terminal gives the names that are known for the 66terminal, separated by `|' characters. 67The first name given is the most common abbreviation for the terminal. 68The last name given should be a long name fully identifying the terminal, 69and all others are understood as synonyms for the terminal name. 70All names but the last should be in lower case and contain no blanks; 71the last name may well contain upper case characters and blanks for 72readability. 73.Pp 74Terminal names (except for the last, verbose entry) 75should be chosen using the following conventions. 76The particular piece of hardware making up the terminal 77should have a root name chosen, thus 78.Dq hp2621 79This name should not contain hyphens. 80Modes that the hardware can be in 81or user preferences 82should be indicated by appending a hyphen and an indicator of the mode. 83Therefore, a 84.Dq vt100 85in 132-column mode would be 86.Dq vt100-w . 87The following suffixes should be used where possible: 88.Pp 89.Bd -filled -offset indent 90.Bl -column indent "With automatic margins (usually default)xx" 91.Sy Suffix Meaning Example 92-w Wide mode (more than 80 columns) vt100-w 93-am With automatic margins (usually default) vt100-am 94-nam Without automatic margins vt100-nam 95.Pf \- Ar n Ta No "Number of lines on screen aaa-60" 96-na No arrow keys (leave them in local) concept100-na 97.Pf \- Ar \&np Ta No "Number of pages of memory concept100-4p" 98-rv Reverse video concept100-rv 99.El 100.Ed 101.Sh CAPABILITIES 102The characters in the 103.Em Notes 104function 105field in the table have the following meanings 106(more than one may apply to a capability): 107.Pp 108.Bd -unfilled -offset indent 109N indicates numeric parameter(s) 110P indicates that padding may be specified 111* indicates that padding may be based on the number of lines affected 112o indicates capability is obsolete 113.Ed 114.Pp 115.Dq Obsolete 116capabilities have no 117.Em terminfo 118equivalents, 119since they were considered useless, 120or are subsumed by other capabilities. 121New software should not rely on them at all. 122.Pp 123.Bl -column indent indent indent 124.Sy Name Type Notes Description 125functions 126.It "ae str (P) End alternate character set." 127.It AL str (NP*) Add" 128.Em n 129new blank lines 130.It "al str (P*) Add new blank line." 131.It "am bool Terminal has automatic margins." 132.It "as str (P) Start alternate character set." 133.It "bc str (o) Backspace if not." 134.Sy \&^H . 135.It "bl str (P) Audible signal (bell)." 136.It "bs bool (o) Terminal can backspace with" 137.Sy \&^H . 138.It "bt str (P) Back tab." 139.It "bw bool " Ta Sy \&le 140(backspace) wraps from column 0 to last column. 141.It "CC str Terminal settable command character in prototype." 142.It "cd str (P*) Clear to end of display." 143.It "ce str (P) Clear to end of line." 144.It "ch str (NP) Set cursor column (horizontal position)." 145.It "cl str (P*) Clear screen and home cursor." 146.It "CM str (NP) Memory-relative cursor addressing." 147.It "cm str (NP) Screen-relative cursor motion." 148.It "co num Number of columns in a line (See" 149.Sx BUGS 150section below). 151.It "cr str (P) Carriage return." 152.It "cs str (NP) Change scrolling region (VT100)." 153.It "ct str (P) Clear all tab stops." 154.It "cv str (NP) Set cursor row (vertical position)." 155.It "da bool Display may be retained above the screen." 156.It "dB num (o) Milliseconds of" 157.Sy \&bs 158delay needed (default 0). 159.It "db bool Display may be retained below the screen." 160.It "DC str (NP*) Delete" 161.Em n 162characters. 163.It "dC num (o) Milliseconds of" 164.Sy \&cr 165delay needed (default 0). 166.It "dc str (P*) Delete character." 167.It "dF num (o) Milliseconds of" 168.Sy \&ff 169delay needed (default 0). 170.It "DL str (NP*) Delete" 171.Ar n 172lines. 173.It "dl str (P*) Delete line." 174.It "dm str Enter delete mode." 175.It "dN num (o) Milliseconds of 176.Sy \&nl 177delay needed (default 0). 178.It "DO str (NP*) Move cursor down: 179.Ar n 180lines. 181.It "do str Down one line." 182.It "ds str Disable status line." 183.It "dT num (o) Milliseconds of horizontal tab delay needed (default 0)." 184.It "dV num (o) Milliseconds of vertical tab delay needed (default 0)." 185.It "ec str (NP) Erase" 186.Ar n 187characters. 188.It "ed str End delete mode." 189.It "ei str End insert mode." 190.It "eo bool Can erase overstrikes with a blank." 191.It "EP bool (o) Even parity." 192.It "es bool Escape can be used on the status line." 193.It "ff str (P*) Hardcopy terminal page eject." 194.It "fs str Return from status line." 195.It "gn bool Generic line type, for example dialup, switch)." 196.It "hc bool Hardcopy terminal." 197.It "HD bool (o) Half-duplex." 198.It "hd str Half-line down (forward 1/2 linefeed)." 199.It "ho str (P) Home cursor." 200.It "hs bool Has extra" 201.Dq status line . 202.It "hu str Half-line up (reverse 1/2 linefeed)." 203.It "hz bool Cannot print ``~'' (Hazeltine)." 204.It "i1-i3 str Terminal initialization strings" 205.Pf ( Xr terminfo 206only) 207.It "IC str (NP*) Insert" 208.Ar n 209blank characters. 210.It "ic str (P*) Insert character." 211.It "if str Name of file containing initialization string." 212.It "im str Enter insert mode." 213.It "in bool Insert mode distinguishes nulls." 214.It "iP str Pathname of program for initialization" 215.Pf ( Xr terminfo 216only). 217.It "ip str (P*) Insert pad after character inserted." 218.It "is str Terminal initialization string" 219.Pf ( Nm termcap 220only). 221.It "it num Tabs initially every" 222.Ar n 223positions. 224.It "K1 str Sent by keypad upper left." 225.It "K2 str Sent by keypad upper right." 226.It "K3 str Sent by keypad center." 227.It "K4 str Sent by keypad lower left." 228.It "K5 str Sent by keypad lower right." 229.It "k0-k9 str Sent by function keys 0-9." 230.It "kA str Sent by insert-line key." 231.It "ka str Sent by clear-all-tabs key." 232.It "kb str Sent by backspace key." 233.It "kC str Sent by clear-screen or erase key." 234.It "kD str Sent by delete-character key." 235.It "kd str Sent by down-arrow key." 236.It "kE str Sent by clear-to-end-of-line key." 237.It "ke str Out of" 238.Dq keypad transmit 239mode. 240.It "kF str Sent by scroll-forward/down key." 241.It "kH str Sent by home-down key." 242.It "kh str Sent by home key." 243.It "kI str Sent by insert-character or enter-insert-mode key." 244.It "kL str Sent by delete-line key." 245.It "kl str Sent by left-arrow key." 246.It "kM str Sent by insert key while in insert mode." 247.It "km bool Has a" 248.Dq meta 249key (shift, sets parity bit). 250.It "kN str Sent by next-page key." 251.It "kn num (o) Number of function" 252.Pq Sy \&k\&0 Ns \- Sy \&k\&9 253keys (default 0). 254.It "ko str (o) Termcap entries for other non-function keys." 255.It "kP str Sent by previous-page key." 256.It "kR str Sent by scroll-backward/up key." 257.It "kr str Sent by right-arrow key." 258.It "kS str Sent by clear-to-end-of-screen key." 259.It "ks str Put terminal in" 260.Dq keypad transmit 261mode. 262.It "kT str Sent by set-tab key." 263.It "kt str Sent by clear-tab key." 264.It "ku str Sent by up-arrow key." 265.It "l0-l9 str Labels on function keys if not" 266.Dq \&f Ns Em n . 267.It "LC bool (o) Lower-case only." 268.It "LE str (NP) Move cursor left" 269.Ar n 270positions. 271.It "le str (P) Move cursor left one position." 272.It "li num Number of lines on screen or page (See" 273.Sx BUGS 274section below) 275.It "ll str Last line, first column 276.It "lm num Lines of memory if >" Sy \&li 277(0 means varies). 278.It "ma str (o) Arrow key map (used by" 279.Xr \&vi 280version 2 only). 281.It "mb str Turn on blinking attribute." 282.It "md str Turn on bold (extra bright) attribute." 283.It "me str Turn off all attributes." 284.It "mh str Turn on half-bright attribute." 285.It "mi bool Safe to move while in insert mode." 286.It "mk str Turn on blank attribute (characters invisible)." 287.It "ml str (o) Memory lock on above cursor." 288.It "mm str Turn on" 289.Dq meta mode 290(8th bit). 291.It "mo str Turn off" 292.Dq meta mode . 293.It "mp str Turn on protected attribute." 294.It "mr str Turn on reverse-video attribute." 295.It "ms bool Safe to move in standout modes." 296.It "mu str (o) Memory unlock (turn off memory lock)." 297.It "nc bool (o) No correctly-working" 298.Sy \&cr 299(Datamedia 2500, Hazeltine 2000). 300.It "nd str Non-destructive space (cursor right)." 301.It "NL bool (o)" Ta Sy \&\en No "is newline, not line feed." 302.It "nl str (o) Newline character if not" Sy \en . 303.It "ns bool (o) Terminal is a" Tn CRT No "but doesn't scroll." 304.It "nw str (P) Newline (behaves like" 305.Sy \&cr 306followed by 307.Sy \&do ). 308.It "OP bool (o) Odd parity." 309.It "os bool Terminal overstrikes." 310.It "pb num Lowest baud where delays are required." 311.It "pc str Pad character (default" Tn NUL ). 312.It "pf str Turn off the printer." 313.It "pk str Program function key" 314.Em n 315to type string 316.Em s 317.Pf ( Xr terminfo 318only). 319.It "pl str Program function key" 320.Em n 321to execute string 322.Em s 323.Pf ( Xr terminfo 324only). 325.It "pO str (N) Turn on the printer for" 326.Em n 327bytes. 328.It "po str Turn on the printer." 329.It "ps str Print contents of the screen." 330.It "pt bool (o) Has hardware tabs (may need to be set with" 331.Sy \&is ). 332.It "px str Program function key" 333.Em n 334to transmit string 335.Em s 336.Pf ( Xr terminfo 337only). 338.It "r1-r3 str Reset terminal completely to sane modes" 339.Pf ( Xr terminfo 340only). 341.It "rc str (P) Restore cursor to position of last" 342.Sy \&sc . 343.It "rf str Name of file containing reset codes." 344.It "RI str (NP) Move cursor right" 345.Em n 346positions. 347.It "rp str (NP*) Repeat character" 348.Em c n 349times. 350.It "rs str Reset terminal completely to sane modes" 351.Pf ( Nm termcap 352only). 353.It "sa str (NP) Define the video attributes." 354.It "sc str (P) Save cursor position." 355.It "se str End standout mode." 356.It "SF str (NP*) Scroll forward" 357.Em n 358lines. 359.It "sf str (P) Scroll text up." 360.It "sg num Number of garbage chars left by" 361.Sy \&so 362or 363.Sy \&se 364(default 0). 365.It "so str Begin standout mode." 366.It "SR str (NP*) Scroll backward" 367.Em n 368lines. 369.It "sr str (P) Scroll text down." 370.It "st str Set a tab in all rows, current column." 371.It "ta str (P) Tab to next 8-position hardware tab stop." 372.It "tc str Entry of similar terminal \- must be last." 373.It "te str String to end programs that use" 374.Nm termcap . 375.It "ti str String to begin programs that use" 376.Nm termcap . 377.It "ts str (N) Go to status line, column" 378.Em n . 379.It "UC bool (o) Upper-case only." 380.It "uc str Underscore one character and move past it." 381.It "ue str End underscore mode." 382.It "ug num Number of garbage chars left by" 383.Sy \&us 384or 385.Sy \&ue 386(default 0). 387.It "ul bool Underline character overstrikes." 388.It "UP str (NP*) Move cursor up" 389.Em n 390lines. 391.It "up str Upline (cursor up)." 392.It "us str Start underscore mode." 393.It "vb str Visible bell (must not move cursor)." 394.It "ve str Make cursor appear normal (undo" 395.Sy \&vs Ns / Sy \&vi ) . 396.It "vi str Make cursor invisible." 397.It "vs str Make cursor very visible." 398.It "vt num Virtual terminal number (not supported on all systems)." 399.It "wi str (N) Set current window." 400.It "ws num Number of columns in status line." 401.It "xb bool Beehive" 402.Pf ( "f1=" Dv ESC , 403.Pf "f2=" Sy \&^C ) . 404.It "xn bool Newline ignored after 80 cols (Concept)." 405.It "xo bool Terminal uses xoff/xon" 406.Pq Dv DC3 Ns / Ns Dv DC1 407handshaking. 408.It "xr bool (o) Return acts like" 409.Sy "ce cr nl" 410(Delta Data). 411.It "xs bool Standout not erased by overwriting (Hewlett-Packard)." 412.It "xt bool Tabs ruin, magic" 413.SY \&so 414char (Teleray 1061). 415.It "xx bool (o) Tektronix 4025 insert-line." 416.El 417.Ss A Sample Entry 418The following entry, which describes the Concept\-100, is among the more 419complex entries in the 420.Nm termcap 421file as of this writing. 422.Pp 423.Bd -literal 424ca\||\|concept100\||\|c100\||\|concept\||\|c104\||\|concept100-4p\||\|HDS Concept\-100:\e 425 :al=3*\eE^R:am:bl=^G:cd=16*\eE^C:ce=16\eE^U:cl=2*^L:cm=\eEa%+ %+ :\e 426 :co#80:.cr=9^M:db:dc=16\eE^A:dl=3*\eE^B:do=^J:ei=\eE\e200:eo:im=\eE^P:in:\e 427 :ip=16*:is=\eEU\eEf\eE7\eE5\eE8\eEl\eENH\eEK\eE\e200\eEo&\e200\eEo\e47\eE:k1=\eE5:\e 428 :k2=\eE6:k3=\eE7:kb=^h:kd=\eE<:ke=\eEx:kh=\eE?:kl=\eE>:kr=\eE=:ks=\eEX:\e 429 :ku=\eE;:le=^H:li#24:mb=\eEC:me=\eEN\e200:mh=\eEE:mi:mk=\eEH:mp=\eEI:\e 430 :mr=\eED:nd=\eE=:pb#9600:rp=0.2*\eEr%.%+ :se=\eEd\eEe:sf=^J:so=\eEE\eED:\e 431 :.ta=8\et:te=\eEv \e200\e200\e200\e200\e200\e200\eEp\er\en:\e 432 :ti=\eEU\eEv 8p\eEp\er:ue=\eEg:ul:up=\eE;:us=\eEG:\e 433 :vb=\eEk\e200\e200\e200\e200\e200\e200\e200\e200\e200\e200\e200\e200\e200\e200\eEK:\e 434 :ve=\eEw:vs=\eEW:vt#8:xn:\e 435 :bs:cr=^M:dC#9:dT#8:nl=^J:ta=^I:pt: 436.Ed 437.Pp 438Entries may continue onto multiple lines by giving a \e as the last 439character of a line, and empty fields 440may be included for readability (here between the last field on a line 441and the first field on the next). 442Comments may be included on lines beginning with 443.Dq # . 444.Ss Types of Capabilities 445Capabilities in 446.Nm termcap 447are of three types: Boolean capabilities, 448which indicate particular features that the terminal has; 449numeric capabilities, 450giving the size of the display or the size of other attributes; 451and string capabilities, 452which give character sequences that can be used to perform particular 453terminal operations. 454All capabilities have two-letter codes. 455For instance, the fact that 456the Concept has 457.Em automatic margins 458(an automatic return and linefeed 459when the end of a line is reached) is indicated by the Boolean capability 460.Sy \&am . 461Hence the description of the Concept includes 462.Sy \&am . 463.Pp 464Numeric capabilities are followed by the character `#' then the value. 465In the example above 466.Sy \&co , 467which indicates the number of columns the display has, 468gives the value `80' for the Concept. 469.Pp 470Finally, string-valued capabilities, such as 471.Sy \&ce 472(clear-to-end-of-line 473sequence) are given by the two-letter code, an `=', then a string 474ending at the next following `:'. 475A delay in milliseconds may appear after 476the `=' in such a capability, 477which causes padding characters to be supplied by 478.Xr tputs 479after the remainder of the string is sent to provide this delay. 480The delay can be either a number, 481such as `20', or a number followed by 482an `*', 483such as `3*'. 484An `*' indicates that the padding required is proportional 485to the number of lines affected by the operation, and the amount given is 486the per-affected-line padding required. 487(In the case of insert-character, 488the factor is still the number of 489.Em lines 490affected; 491this is always 1 unless the terminal has 492.Sy \&in 493and the software uses it.) 494When an `*' is specified, it is sometimes useful to give a delay of the form 495`3.5' to specify a delay per line to tenths of milliseconds. 496(Only one decimal place is allowed.) 497.Pp 498A number of escape sequences are provided in the string-valued capabilities 499for easy encoding of control characters there. 500.Sy \&\eE 501maps to an 502.Dv ESC 503character, 504.Sy \&^X 505maps to a control-X for any appropriate X, 506and the sequences 507.Sy \&\en 508.Sy \&\er 509.Sy \&\et 510.Sy \&\eb 511.Sy \&\ef 512map to linefeed, return, tab, backspace, and formfeed, respectively. 513Finally, characters may be given as three octal digits after a 514.Sy \&\e , 515and the characters 516.Sy \&^ 517and 518.Sy \&\e 519may be given as 520.Sy \&\e^ 521and 522.Sy \&\e\e . 523If it is necessary to place a 524.Sy \&: 525in a capability it must be escaped in 526octal as 527.Sy \&\e072 . 528If it is necessary to place a 529.Dv NUL 530character in a string capability it 531must be encoded as 532.Sy \&\e200 . 533(The routines that deal with 534.Nm termcap 535use C strings and strip the high bits of the output very late, so that 536a 537.Sy \&\e200 538comes out as a 539.Sy \&\e000 540would.) 541.Pp 542Sometimes individual capabilities must be commented out. 543To do this, put a period before the capability name. 544For example, see the first 545.Sy \&cr 546and 547.Sy \&ta 548in the example above. 549.Ss Preparing Descriptions 550The most effective way to prepare a terminal description is by imitating 551the description of a similar terminal in 552.Nm termcap 553and to build up a description gradually, using partial descriptions 554with 555.Xr \&vi 556to check that they are correct. 557Be aware that a very unusual terminal may expose deficiencies in 558the ability of the 559.Nm termcap 560file to describe it 561or bugs in 562.Xr \&vi . 563To easily test a new terminal description you are working on 564you can put it in your home directory in a file called 565.Pa .termcap 566and programs will look there before looking in 567.Pa /usr/share/misc/termcap . 568You can also set the environment variable 569.Ev TERMPATH 570to a list of absolute file pathnames (separated by spaces or colons), 571one of which contains the description you are working on, 572and programs will search them in the order listed, and nowhere else. 573See 574.Xr termcap 3 . 575The 576.Ev TERMCAP 577environment variable is usually set to the 578.Nm termcap 579entry itself 580to avoid reading files when starting up a program. 581.Pp 582To get the padding for insert-line right 583(if the terminal manufacturer did not document it), 584a severe test is to use 585.Xr \&vi 586to edit 587.Pa /etc/passwd 588at 9600 baud, delete roughly 16 lines from the middle of the screen, 589then hit the `u' key several times quickly. 590If the display messes up, more padding is usually needed. 591A similar test can be used for insert-character. 592.Ss Basic Capabilities 593The number of columns on each line of the display is given by the 594.Sy \&co 595numeric capability. 596If the display is a 597.Tn CRT , 598then the 599number of lines on the screen is given by the 600.Sy \&li 601capability. 602If the display wraps around to the beginning of the next line when 603the cursor reaches the right margin, then it should have the 604.Sy \&am 605capability. 606If the terminal can clear its screen, 607the code to do this is given by the 608.Sy \&cl 609string capability. 610If the terminal overstrikes 611(rather than clearing the position when a character is overwritten), 612it should have the 613.Sy \&os 614capability. 615If the terminal is a printing terminal, 616with no soft copy unit, 617give it both 618.Sy \&hc 619and 620.Sy \&os . 621.Pf ( Sy \&os 622applies to storage scope terminals, 623such as the Tektronix 4010 series, 624as well as to hard copy and 625.Tn APL 626terminals.) 627If there is a code to move the cursor to the left edge of the current row, 628give this as 629.Sy \&cr . 630(Normally this will be carriage-return, 631.Sy \&^M . ) 632If there is a code to produce an audible signal (bell, beep, 633etc. ) , 634give this as 635.Sy \&bl . 636.Pp 637If there is a code (such as backspace) 638to move the cursor one position to the left, 639that capability should be given as 640.Sy \&le . 641Similarly, 642codes to move to the right, up, and down 643should be given as 644.Sy \&nd , 645.Sy \&up , 646and 647.Sy \&do , 648respectively. 649These 650.Em local cursor motions 651should not alter the text they pass over; 652for example, you would not normally use 653.Dq nd=\ \& 654unless the terminal has the 655.Sy \&os 656capability, 657because the space would erase the character moved over. 658.Pp 659A very important point here is that the local cursor motions encoded 660in 661.Nm termcap 662have undefined behavior at the left and top edges of a 663.Tn CRT 664display. 665Programs should never attempt to backspace around the left edge, 666unless 667.Sy \&bw 668is given, and never attempt to go up off the top 669using local cursor motions. 670.Pp 671In order to scroll text up, 672a program goes to the bottom left corner of the screen and sends the 673.Sy \&sf 674(index) string. 675To scroll text down, 676a program goes to the top left corner of the screen and sends the 677.Sy \&sr 678(reverse index) string. 679The strings 680.Sy \&sf 681and 682.Sy \&sr 683have undefined behavior 684when not on their respective corners of the screen. 685Parameterized versions of the scrolling sequences are 686.Sy \&SF 687and 688.Sy \&SR , 689which have the same semantics as 690.Sy \&sf 691and 692.Sy \&sr 693except that they take one parameter 694and scroll that many lines. 695They also have undefined behavior 696except at the appropriate corner of the screen. 697.Pp 698The 699.Sy \&am 700capability tells whether the cursor sticks at the right 701edge of the screen when text is output there, 702but this does not necessarily apply to 703.Sy \&nd 704from the last column. 705Leftward local motion is defined from the left edge only when 706.Sy \&bw 707is given; then an 708.Sy \&le 709from the left edge will move to the right edge of the previous row. 710This is useful for drawing a box around the edge of the screen, 711for example. 712If the terminal has switch-selectable automatic margins, 713the 714.Nm termcap 715description usually assumes that this feature is on, 716.Em i.e . , 717.Sy \&am . 718If the terminal has a command 719that moves to the first column of the next line, 720that command can be given as 721.Sy \&nw 722(newline). 723It is permissible for this to clear the remainder of the current line, 724so if the terminal has no correctly-working 725.Tn \&CR 726and 727.Tn \&LF 728it may still be possible to craft a working 729.Sy \&nw 730out of one or both of them. 731.Pp 732These capabilities suffice to describe hardcopy and 733.Dq glass-tty 734terminals. 735Thus the Teletype model 33 is described as 736.Bd -literal -offset indent 737T3\||\|tty33\||\|33\||\|tty\||\|Teletype model 33:\e 738 :bl=^G:co#72:cr=^M:do=^J:hc:os: 739.Ed 740.Pp 741and the Lear Siegler 742.Tn ADM Ns \-3 743is described as 744.Bd -literal -offset indent 745l3\||\|adm3\||\|3\||\|LSI \s-1ADM\s0-3:\e 746:am:bl=^G:cl=^Z:co#80:cr=^M:do=^J:le=^H:li#24:sf=^J: 747.Ed 748.Ss Parameterized Strings 749Cursor addressing and other strings requiring parameters 750are described by a 751parameterized string capability, with 752.Xr printf 3 Ns \-like 753escapes 754.Sy \&%x 755in it, 756while other characters are passed through unchanged. 757For example, to address the cursor the 758.Sy \&cm 759capability is given, using two parameters: the row and column to move to. 760(Rows and columns are numbered from zero and refer to the physical screen 761visible to the user, not to any unseen memory. 762If the terminal has memory-relative cursor addressing, 763that can be indicated by an analogous 764.Sy \&CM 765capability.) 766.Pp 767The 768.Sy \&% 769encodings have the following meanings: 770.Bl -column xxxxx 771.It "%% output `%'" 772.It "%d output value as in" 773.Xr printf 774%d 775.It "%2 output value as in" 776.Xr printf 777%2d 778.It "%3 output value as in" 779.Xr printf 780%3d 781.It "%. output value as in" 782.Xr printf 783%c 784.It "%+" Ns Em x Ta No add 785.Em x 786to value, then do %. 787.It "%>" Ns Em \&xy Ta No if 788value > 789.Em x 790then add 791.Em y , 792no output 793.It "%r reverse order of two parameters, no output" 794.It "%i increment by one, no output" 795.It "%n exclusive-or all parameters with 0140 (Datamedia 2500)" 796.It "%B" Ta Tn BCD No "(16*(value/10)) + (value%10), no output" 797.It "%D Reverse coding (value \- 2*(value%16)), no output (Delta Data)." 798.El 799.Pp 800Consider the Hewlett-Packard 2645, which, to get to row 3 and column 12, needs 801to be sent 802.Dq \eE&a12c03Y 803padded for 6 milliseconds. 804Note that the order 805of the row and column coordinates is reversed here 806and that the row and column 807are sent as two-digit integers. 808Thus its 809.Sy \&cm 810capability is 811.Dq Li cm=6\eE&%r%2c%2Y . 812.Pp 813The Datamedia 2500 needs the current row and column sent 814encoded in binary using 815.Dq \&%. . 816Terminals that use 817.Dq \&%. 818need to be able to 819backspace the cursor 820.Po Sy \&le Pc 821and to move the cursor up one line on the screen 822.Po Sy \&up Pc . 823This is necessary because it is not always safe to transmit 824.Sy \&\en , 825.Sy \&^D , 826and 827.Sy \&\er , 828as the system may change or discard them. 829(Programs using 830.Nm termcap 831must set terminal modes so that tabs are not expanded, so 832.Sy \&\et 833is safe to send. 834This turns out to be essential for the Ann Arbor 4080.) 835.Pp 836A final example is the Lear Siegler 837.Tn ADM Ns \-3a, 838which offsets row and column 839by a blank character, thus 840.Dq Li cm=\eE=%+ %+\ \& . 841.Pp 842Row or column absolute cursor addressing 843can be given as single parameter capabilities 844.Sy \&ch 845(horizontal position absolute) and 846.Sy \&cv 847(vertical position absolute). 848Sometimes these are shorter than the more general two-parameter sequence 849(as with the Hewlett-Packard 2645) and can be used in preference to 850.Sy \&cm . 851If there are parameterized local motions 852.Pf ( Em e.g . , 853move 854.Ar n 855positions to the right) 856these can be given as 857.Sy \&DO , 858.Sy \&LE , 859.Sy \&RI , 860and 861.Sy \&UP 862with a single parameter indicating how many positions to move. 863These are primarily useful if the terminal does not have 864.Sy \&cm , 865such as the Tektronix 4025. 866.Ss Cursor Motions 867.Pp 868If the terminal has a fast way to home the cursor 869(to the very upper left corner of the screen), this can be given as 870.Sy \&ho . 871Similarly, a fast way of getting to the lower left-hand corner 872can be given as 873.Sy \&ll ; 874this may involve going up with 875.Sy \&up 876from the home position, 877but a program should never do this itself (unless 878.Sy \&ll 879does), because it can 880make no assumption about the effect of moving up from the home position. 881Note that the home position is the same as 882cursor address (0,0): to the top left corner of the screen, not of memory. 883(Therefore, the 884.Dq \eEH 885sequence on Hewlett-Packard terminals 886cannot be used for 887.Sy \&ho . ) 888.Ss Area Clears 889If the terminal can clear from the current position to the end of the 890line, leaving the cursor where it is, this should be given as 891.Sy \&ce . 892If the terminal can clear from the current position to the end of the 893display, this should be given as 894.Sy \&cd . 895.Sy \&cd 896must only be invoked from the first column of a line. 897(Therefore, 898it can be simulated by a request to delete a large number of lines, 899if a true 900.Sy \&cd 901is not available.) 902.Ss Insert/Delete Line 903If the terminal can open a new blank line 904before the line containing the cursor, 905this should be given as 906.Sy \&al ; 907this must be invoked only from the first 908position of a line. 909The cursor must then appear at the left of the newly blank line. 910If the terminal can delete the line that the cursor is on, this 911should be given as 912.Sy \&dl ; 913this must only be used from the first position on 914the line to be deleted. 915Versions of 916.Sy \&al 917and 918.Sy \&dl 919which take a single parameter 920and insert or delete that many lines 921can be given as 922.Sy \&AL 923and 924.Sy \&DL . 925If the terminal has a settable scrolling region 926(like the VT100), 927the command to set this can be described with the 928.Sy \&cs 929capability, 930which takes two parameters: the top and bottom lines of the scrolling region. 931The cursor position is, alas, undefined after using this command. 932It is possible to get the effect of insert or delete line 933using this command \(em the 934.Sy \&sc 935and 936.Sy \&rc 937(save and restore cursor) commands are also useful. 938Inserting lines at the top or bottom of the screen can also be done using 939.Sy \&sr 940or 941.Sy \&sf 942on many terminals without a true insert/delete line, 943and is often faster even on terminals with those features. 944.Pp 945If the terminal has the ability to define a window as part of memory 946which all commands affect, it should be given as the parameterized string 947.Sy \&wi . 948The four parameters are the starting and ending lines in memory 949and the starting and ending columns in memory, in that order. 950(This 951.Xr terminfo 952capability is described for completeness. 953It is unlikely that any 954.Nm termcap Ns \- using 955program will support it.) 956.Pp 957If the terminal can retain display memory above the screen, then the 958.Sy \&da 959capability should be given; 960if display memory can be retained 961below, then 962.Sy \&db 963should be given. 964These indicate 965that deleting a line or scrolling may bring non-blank lines up from below 966or that scrolling back with 967.Sy \&sr 968may bring down non-blank lines. 969.Ss Insert/Delete Character 970There are two basic kinds of intelligent terminals with respect to 971insert/delete character that can be described using 972.Nm termcap . 973The most common insert/delete character operations affect only the characters 974on the current line and shift characters off the end of the line rigidly. 975Other terminals, such as the Concept\-100 and the Perkin Elmer Owl, make 976a distinction between typed and untyped blanks on the screen, shifting 977upon an insert or delete only to an untyped blank on the screen which is 978either eliminated or expanded to two untyped blanks. 979You can determine 980the kind of terminal you have by clearing the screen then typing 981text separated by cursor motions. 982Type 983.Dq Li abc\ \ \ \ def 984using local 985cursor motions (not spaces) between the 986.Dq abc 987and the 988.Dq def . 989Then position the cursor before the 990.Dq abc 991and put the terminal in insert 992mode. 993If typing characters causes the rest of the line to shift 994rigidly and characters to fall off the end, then your terminal does 995not distinguish between blanks and untyped positions. 996If the 997.Dq abc 998shifts over to the 999.Dq def 1000which then move together around the end of the 1001current line and onto the next as you insert, then you have the second type of 1002terminal and should give the capability 1003.Sy \&in , 1004which stands for 1005.Dq insert null . 1006While these are two logically separate attributes 1007(one line 1008.Em \&vs . 1009multi-line insert mode, 1010and special treatment of untyped spaces), 1011we have seen no terminals whose insert 1012mode cannot be described with the single attribute. 1013.Pp 1014.Nm Termcap 1015can describe both terminals that have an insert mode and terminals 1016that send a simple sequence to open a blank position on the current line. 1017Give as 1018.Sy \&im 1019the sequence to get into insert mode. 1020Give as 1021.Sy \&ei 1022the sequence to leave insert mode. 1023Now give as 1024.Sy \&ic 1025any sequence that needs to be sent just before 1026each character to be inserted. 1027Most terminals with a true insert mode 1028will not give 1029.Sy \&ic ; 1030terminals that use a sequence to open a screen 1031position should give it here. 1032(If your terminal has both, 1033insert mode is usually preferable to 1034.Sy \&ic . 1035Do not give both unless the terminal actually requires both to be used 1036in combination.) 1037If post-insert padding is needed, give this as a number of milliseconds 1038in 1039.Sy \&ip 1040(a string option). 1041Any other sequence that may need to be 1042sent after insertion of a single character can also be given in 1043.Sy \&ip . 1044If your terminal needs to be placed into an `insert mode' 1045and needs a special code preceding each inserted character, 1046then both 1047.Sy \&im Ns / Sy \&ei 1048and 1049.Sy \&ic 1050can be given, and both will be used. 1051The 1052.Sy \&IC 1053capability, with one parameter 1054.Em n , 1055will repeat the effects of 1056.Sy \&ic 1057.Em n 1058times. 1059.Pp 1060It is occasionally necessary to move around while in insert mode 1061to delete characters on the same line 1062.Pf ( Em e.g . , 1063if there is a tab after 1064the insertion position). 1065If your terminal allows motion while in 1066insert mode, you can give the capability 1067.Sy \&mi 1068to speed up inserting 1069in this case. 1070Omitting 1071.Sy \&mi 1072will affect only speed. 1073Some terminals 1074(notably Datamedia's) must not have 1075.Sy \&mi 1076because of the way their 1077insert mode works. 1078.Pp 1079Finally, you can specify 1080.Sy \&dc 1081to delete a single character, 1082.Sy \&DC 1083with one parameter 1084.Em n 1085to delete 1086.Em n 1087characters, 1088and delete mode by giving 1089.Sy \&dm 1090and 1091.Sy \&ed 1092to enter and exit delete mode 1093(which is any mode the terminal needs to be placed in for 1094.Sy \&dc 1095to work). 1096.Ss Highlighting, Underlining, and Visible Bells 1097If your terminal has one or more kinds of display attributes, 1098these can be represented in a number of different ways. 1099You should choose one display form as 1100.Em standout mode , 1101representing a good high-contrast, easy-on-the-eyes format 1102for highlighting error messages and other attention getters. 1103(If you have a choice, reverse video plus half-bright is good, 1104or reverse video alone.) 1105The sequences to enter and exit standout mode 1106are given as 1107.Sy \&so 1108and 1109.Sy \&se , 1110respectively. 1111If the code to change into or out of standout 1112mode leaves one or even two blank spaces or garbage characters on the screen, 1113as the 1114.Tn TVI 1115912 and Teleray 1061 do, 1116then 1117.Sy \&sg 1118should be given to tell how many characters are left. 1119.Pp 1120Codes to begin underlining and end underlining can be given as 1121.Sy \&us 1122and 1123.Sy \&ue , 1124respectively. 1125Underline mode change garbage is specified by 1126.Sy \&ug , 1127similar to 1128.Sy \&sg . 1129If the terminal has a code to underline the current character and move 1130the cursor one position to the right, 1131such as the Microterm Mime, 1132this can be given as 1133.Sy \&uc . 1134.Pp 1135Other capabilities to enter various highlighting modes include 1136.Sy \&mb 1137(blinking), 1138.Sy \&md 1139(bold or extra bright), 1140.Sy \&mh 1141(dim or half-bright), 1142.Sy \&mk 1143(blanking or invisible text), 1144.Sy \&mp 1145(protected), 1146.Sy \&mr 1147(reverse video), 1148.Sy \&me 1149(turn off 1150.Em all 1151attribute modes), 1152.Sy \&as 1153(enter alternate character set mode), and 1154.Sy \&ae 1155(exit alternate character set mode). 1156Turning on any of these modes singly may or may not turn off other modes. 1157.Pp 1158If there is a sequence to set arbitrary combinations of mode, 1159this should be given as 1160.Sy \&sa 1161(set attributes), taking 9 parameters. 1162Each parameter is either 0 or 1, 1163as the corresponding attributes is on or off. 1164The 9 parameters are, in order: standout, underline, reverse, blink, 1165dim, bold, blank, protect, and alternate character set. 1166Not all modes need be supported by 1167.Sy \&sa , 1168only those for which corresponding attribute commands exist. 1169(It is unlikely that a 1170.Nm termcap Ns \-using 1171program will support this capability, which is defined for compatibility 1172with 1173.Xr terminfo . ) 1174.Pp 1175Terminals with the 1176.Dq magic cookie 1177glitches 1178.Pf ( Sy \&sg 1179and 1180.Sy \&ug ) , 1181rather than maintaining extra attribute bits for each character cell, 1182instead deposit special 1183.Dq cookies , 1184or 1185.Dq garbage characters ,, 1186when they receive mode-setting sequences, 1187which affect the display algorithm. 1188.Pp 1189Some terminals, 1190such as the Hewlett-Packard 2621, 1191automatically leave standout 1192mode when they move to a new line or when the cursor is addressed. 1193Programs using standout mode 1194should exit standout mode on such terminals 1195before moving the cursor or sending a newline. 1196On terminals where this is not a problem, 1197the 1198.Sy \&ms 1199capability should be present 1200to say that this overhead is unnecessary. 1201.Pp 1202If the terminal has 1203a way of flashing the screen to indicate an error quietly 1204(a bell replacement), 1205this can be given as 1206.Sy \&vb ; 1207it must not move the cursor. 1208.Pp 1209If the cursor needs to be made more visible than normal 1210when it is not on the bottom line 1211(to change, for example, a non-blinking underline into an easier-to-find 1212block or blinking underline), 1213give this sequence as 1214.Sy \&vs . 1215If there is a way to make the cursor completely invisible, give that as 1216.Sy \&vi . 1217The capability 1218.Sy \&ve , 1219which undoes the effects of both of these modes, 1220should also be given. 1221.Pp 1222If your terminal correctly displays underlined characters 1223(with no special codes needed) 1224even though it does not overstrike, 1225then you should give the capability 1226.Sy \&ul . 1227If overstrikes are erasable with a blank, 1228this should be indicated by giving 1229.Sy \&eo . 1230.Ss Keypad 1231If the terminal has a keypad that transmits codes when the keys are pressed, 1232this information can be given. 1233Note that it is not possible to handle 1234terminals where the keypad only works in local mode 1235(this applies, for example, to the unshifted Hewlett-Packard 2621 keys). 1236If the keypad can be set to transmit or not transmit, 1237give these codes as 1238.Sy \&ks 1239and 1240.Sy \&ke . 1241Otherwise the keypad is assumed to always transmit. 1242The codes sent by the left-arrow, right-arrow, up-arrow, down-arrow, 1243and home keys can be given as 1244.Sy \&kl , 1245.Sy \&kr , 1246.Sy \&ku , 1247.Sy \&kd , 1248and 1249.Sy \&kh , 1250respectively. 1251If there are function keys such as f0, f1, ..., f9, the codes they send 1252can be given as 1253.Sy \&k0 , 1254.Sy \&k1 , 1255..., 1256.Sy \&k9 . 1257If these keys have labels other than the default f0 through f9, the labels 1258can be given as 1259.Sy \&l0 , 1260.Sy \&l1 , 1261..., 1262.Sy \&l9 . 1263The codes transmitted by certain other special keys can be given: 1264.Sy \&kH 1265(home down), 1266.Sy \&kb 1267(backspace), 1268.Sy \&ka 1269(clear all tabs), 1270.Sy \&kt 1271(clear the tab stop in this column), 1272.Sy \&kC 1273(clear screen or erase), 1274.Sy \&kD 1275(delete character), 1276.Sy \&kL 1277(delete line), 1278.Sy \&kM 1279(exit insert mode), 1280.Sy \&kE 1281(clear to end of line), 1282.Sy \&kS 1283(clear to end of screen), 1284.Sy \&kI 1285(insert character or enter insert mode), 1286.Sy \&kA 1287(insert line), 1288.Sy \&kN 1289(next page), 1290.Sy \&kP 1291(previous page), 1292.Sy \&kF 1293(scroll forward/down), 1294.Sy \&kR 1295(scroll backward/up), and 1296.Sy \&kT 1297(set a tab stop in this column). 1298In addition, if the keypad has a 3 by 3 array of keys 1299including the four arrow keys, then the other five keys can be given as 1300.Sy \&K1 , 1301.Sy \&K2 , 1302.Sy \&K3 , 1303.Sy \&K4 , 1304and 1305.Sy \&K5 . 1306These keys are useful when the effects of a 3 by 3 directional pad are needed. 1307The obsolete 1308.Sy \&ko 1309capability formerly used to describe 1310.Dq other 1311function keys has been 1312completely supplanted by the above capabilities. 1313.Pp 1314The 1315.Sy \&ma 1316entry is also used to indicate arrow keys on terminals that have 1317single-character arrow keys. 1318It is obsolete but still in use in 1319version 2 of 1320.Sy \&vi 1321which must be run on some minicomputers due to 1322memory limitations. 1323This field is redundant with 1324.Sy \&kl , 1325.Sy \&kr , 1326.Sy \&ku , 1327.Sy \&kd , 1328and 1329.Sy \&kh . 1330It consists of groups of two characters. 1331In each group, the first character is what an arrow key sends, and the 1332second character is the corresponding 1333.Sy \&vi 1334command. 1335These commands are 1336.Ar h 1337for 1338.Sy \&kl , 1339.Ar j 1340for 1341.Sy \&kd , 1342.Ar k 1343for 1344.Sy \&ku , 1345.Ar l 1346for 1347.Sy \&kr , 1348and 1349.Ar H 1350for 1351.Sy \&kh . 1352For example, the Mime would have 1353.Dq Li ma=^Hh^Kj^Zk^Xl 1354indicating arrow keys left (^H), down (^K), up (^Z), and right (^X). 1355(There is no home key on the Mime.) 1356.Ss Tabs and Initialization 1357If the terminal needs to be in a special mode when running 1358a program that uses these capabilities, 1359the codes to enter and exit this mode can be given as 1360.Sy \&ti 1361and 1362.Sy \&te . 1363This arises, for example, from terminals like the Concept with more than 1364one page of memory. 1365If the terminal has only memory-relative cursor addressing and not 1366screen-relative cursor addressing, 1367a screen-sized window must be fixed into 1368the display for cursor addressing to work properly. 1369This is also used for the Tektronix 4025, where 1370.Sy \&ti 1371sets the command character to be the one used by 1372.Nm termcap . 1373.Pp 1374Other capabilities 1375include 1376.Sy \&is , 1377an initialization string for the terminal, 1378and 1379.Sy \&if , 1380the name of a file containing long initialization strings. 1381These strings are expected to set the terminal into modes 1382consistent with the rest of the 1383.Nm termcap 1384description. 1385They are normally sent to the terminal by the 1386.Xr tset 1387program each time the user logs in. 1388They will be printed in the following order: 1389.Sy \&is ; 1390setting tabs using 1391.Sy \&ct 1392and 1393.Sy \&st ; 1394and finally 1395.Sy \&if . 1396.Pf ( Xr Terminfo 1397uses 1398.Sy \&i\&1-i2 1399instead of 1400.Sy \&is 1401and runs the program 1402.Sy \&iP 1403and prints 1404.Sy "\&i\&3" 1405after the other initializations.) 1406A pair of sequences that does a harder reset from a totally unknown state 1407can be analogously given as 1408.Sy \&rs 1409and 1410.Sy \&if . 1411These strings are output by the 1412.Xr reset 1413program, which is used when the terminal gets into a wedged state. 1414.Pf ( Xr Terminfo 1415uses 1416.Sy "\&r1-r3" 1417instead of 1418.Sy \&rs . ) 1419Commands are normally placed in 1420.Sy \&rs 1421and 1422.Sy \&rf 1423only if they produce annoying effects on the screen and are not necessary 1424when logging in. 1425For example, the command to set the VT100 into 80-column mode 1426would normally be part of 1427.Sy \&is , 1428but it causes an annoying glitch of the screen and is not normally needed 1429since the terminal is usually already in 80-column mode. 1430.Pp 1431If the terminal has hardware tabs, 1432the command to advance to the next tab stop can be given as 1433.Sy \&ta 1434(usually 1435.Sy \&^I ) . 1436A 1437.Dq backtab 1438command which moves leftward to the previous tab stop 1439can be given as 1440.Sy \&bt . 1441By convention, 1442if the terminal driver modes indicate that tab stops are being expanded 1443by the computer rather than being sent to the terminal, 1444programs should not use 1445.Sy \&ta 1446or 1447.Sy \&bt 1448even if they are present, 1449since the user may not have the tab stops properly set. 1450If the terminal has hardware tabs that are initially set every 1451.Ar n 1452positions when the terminal is powered up, then the numeric parameter 1453.Sy \&it 1454is given, showing the number of positions between tab stops. 1455This is normally used by the 1456.Xr tset 1457command to determine whether to set the driver mode for hardware tab 1458expansion, and whether to set the tab stops. 1459If the terminal has tab stops that can be saved in nonvolatile memory, the 1460.Nm termcap 1461description can assume that they are properly set. 1462.Pp 1463If there are commands to set and clear tab stops, they can be given as 1464.Sy \&ct 1465(clear all tab stops) and 1466.Sy \&st 1467(set a tab stop in the current column of every row). 1468If a more complex sequence is needed to set the tabs than can be 1469described by this, the sequence can be placed in 1470.Sy \&is 1471or 1472.Sy \&if . 1473.Ss Delays 1474Certain capabilities control padding in the terminal driver. 1475These are primarily needed by hardcopy terminals and are used by the 1476.Xr tset 1477program to set terminal driver modes appropriately. 1478Delays embedded in the capabilities 1479.Sy \&cr , 1480.Sy \&sf , 1481.Sy \&le , 1482.Sy \&ff , 1483and 1484.Sy \&ta 1485will cause the appropriate delay bits to be set in the terminal driver. 1486If 1487.Sy \&pb 1488(padding baud rate) is given, these values can be ignored at baud rates 1489below the value of 1490.Sy \&pb . 1491For 1492.Bx 4.2 1493.Xr tset , 1494the delays are given as numeric capabilities 1495.Sy \&dC , 1496.Sy \&dN , 1497.Sy \&dB , 1498.Sy \&dF , 1499and 1500.Sy \&dT 1501instead. 1502.Ss Miscellaneous 1503If the terminal requires other than a 1504.Dv NUL 1505(zero) character as a pad, 1506this can be given as 1507.Sy \&pc . 1508Only the first character of the 1509.Sy \&pc 1510string is used. 1511.Pp 1512If the terminal has commands to save and restore the position of the 1513cursor, give them as 1514.Sy \&sc 1515and 1516.Sy \&rc . 1517.Pp 1518If the terminal has an extra 1519.Dq status line 1520that is not normally used by 1521software, this fact can be indicated. 1522If the status line is viewed as an extra line below the bottom line, 1523then the capability 1524.Sy \&hs 1525should be given. 1526Special strings to go to a position in the status line and to return 1527from the status line can be given as 1528.Sy \&ts 1529and 1530.Sy \&fs . 1531.Pf ( Xr \&fs 1532must leave the cursor position in the same place that it was before 1533.Sy \&ts . 1534If necessary, the 1535.Sy \&sc 1536and 1537.Sy \&rc 1538strings can be included in 1539.Sy \&ts 1540and 1541.Sy \&fs 1542to get this effect.) 1543The capability 1544.Sy \&ts 1545takes one parameter, which is the column number of the status line 1546to which the cursor is to be moved. 1547If escape sequences and other special commands such as tab work while in 1548the status line, the flag 1549.Sy \&es 1550can be given. 1551A string that turns off the status line (or otherwise erases its contents) 1552should be given as 1553.Sy \&ds . 1554The status line is normally assumed to be the same width as the 1555rest of the screen, 1556.Em i.e . , 1557.Sy \&co . 1558If the status line is a different width (possibly because the terminal 1559does not allow an entire line to be loaded), then its width in columns 1560can be indicated with the numeric parameter 1561.Sy \&ws . 1562.Pp 1563If the terminal can move up or down half a line, this can be 1564indicated with 1565.Sy \&hu 1566(half-line up) and 1567.Sy \&hd 1568(half-line down). 1569This is primarily useful for superscripts and subscripts on hardcopy 1570terminals. 1571If a hardcopy terminal can eject to the next page (form feed), 1572give this as 1573.Sy \&ff 1574(usually 1575.Sy \&^L ) . 1576.Pp 1577If there is a command to repeat a given character a given number of times 1578(to save time transmitting a large number of identical characters), 1579this can be indicated with the parameterized string 1580.Sy \&rp . 1581The first parameter is the character to be repeated and the second is 1582the number of times to repeat it. 1583(This is a 1584.Xr terminfo 1585feature that is unlikely to be supported by a program that uses 1586.Nm termcap . ) 1587.Pp 1588If the terminal has a settable command character, such as the 1589Tektronix 4025, this can be indicated with 1590.Sy \&CC . 1591A prototype command character is chosen which is used in all capabilities. 1592This character is given in the 1593.Sy \&CC 1594capability to identify it. 1595The following convention is supported on some 1596.Ux 1597systems: 1598The environment is to be searched for a 1599.Ev \&CC 1600variable, 1601and if found, 1602all occurrences of the prototype character are replaced by the character 1603in the environment variable. 1604This use of the 1605.Ev \&CC 1606environment variable 1607is a very bad idea, as it conflicts with 1608.Xr make 1 . 1609.Pp 1610Terminal descriptions that do not represent a specific kind of known 1611terminal, such as 1612.Em switch , 1613.Em dialup , 1614.Em patch , 1615and 1616.Xr network , 1617should include the 1618.Sy \&gn 1619(generic) capability so that programs can complain that they do not know 1620how to talk to the terminal. 1621(This capability does not apply to 1622.Em virtual 1623terminal descriptions for which the escape sequences are known.) 1624.Pp 1625If the terminal uses xoff/xon 1626.Pq Tn DC3 Ns / Ns Tn DC1 1627handshaking for flow control, give 1628.Sy \&xo . 1629Padding information should still be included so that routines can make 1630better decisions about costs, but actual pad characters will not be 1631transmitted. 1632.Pp 1633If the terminal has a 1634.Dq meta key 1635which acts as a shift key, setting the 16368th bit of any character transmitted, then this fact can be indicated with 1637.Sy \&km . 1638Otherwise, software will assume that the 8th bit is parity and it will 1639usually be cleared. 1640If strings exist to turn this 1641.Dq meta mode 1642on and off, they can be given as 1643.Sy \&mm 1644and 1645.Sy \&mo . 1646.Pp 1647If the terminal has more lines of memory than will fit on the screen at once, 1648the number of lines of memory can be indicated with 1649.Sy \&lm . 1650An explicit value of 0 indicates that the number of lines is not fixed, 1651but that there is still more memory than fits on the screen. 1652.Pp 1653If the terminal is one of those supported by the 1654.Ux 1655system virtual 1656terminal protocol, the terminal number can be given as 1657.Sy \&vt . 1658.Pp 1659Media copy strings which control an auxiliary printer 1660connected to the terminal can be given as 1661.Sy \&ps : 1662print the contents of the screen; 1663.Sy \&pf : 1664turn off the printer; and 1665.Sy \&po : 1666turn on the printer. 1667When the printer is on, all text sent to the terminal will be sent to the 1668printer. 1669It is undefined whether the text is also displayed on the terminal screen 1670when the printer is on. 1671A variation 1672.Sy \&pO 1673takes one parameter and leaves the printer on for as many characters as the 1674value of the parameter, then turns the printer off. 1675The parameter should not exceed 255. 1676All text, including 1677.Sy \&pf , 1678is transparently passed to the printer while 1679.Sy \&pO 1680is in effect. 1681.Pp 1682Strings to program function keys can be given as 1683.Sy \&pk , 1684.Sy \&pl , 1685and 1686.Sy \&px . 1687Each of these strings takes two parameters: the function key number 1688to program (from 0 to 9) and the string to program it with. 1689Function key numbers out of this range may program undefined keys 1690in a terminal-dependent manner. 1691The differences among the capabilities are that 1692.Sy \&pk 1693causes pressing the given key to be the same as the user typing the given 1694string; 1695.Sy \&pl 1696causes the string to be executed by the terminal in local mode; 1697and 1698.Sy \&px 1699causes the string to be transmitted to the computer. 1700Unfortunately, due to lack of a definition for string parameters in 1701.Nm termcap , 1702only 1703.Xr terminfo 1704supports these capabilities. 1705.Ss Glitches and Braindamage 1706Hazeltine terminals, which do not allow `~' characters to be displayed, 1707should indicate 1708.Sy \&hz . 1709.Pp 1710The 1711.Sy \&nc 1712capability, now obsolete, formerly indicated Datamedia terminals, 1713which echo 1714.Sy \&\er \en 1715for 1716carriage return then ignore a following linefeed. 1717.Pp 1718Terminals that ignore a linefeed immediately after an 1719.Sy \&am 1720wrap, such as the Concept, should indicate 1721.Sy \&xn . 1722.Pp 1723If 1724.Sy \&ce 1725is required to get rid of standout 1726(instead of merely writing normal text on top of it), 1727.Sy \&xs 1728should be given. 1729.Pp 1730Teleray terminals, where tabs turn all characters moved over to blanks, 1731should indicate 1732.Sy \&xt 1733(destructive tabs). 1734This glitch is also taken to mean that it is not possible 1735to position the cursor on top of a \*(lqmagic cookie\*(rq, and that 1736to erase standout mode it is necessary to use delete and insert line. 1737.Pp 1738The Beehive Superbee, which is unable to correctly transmit the 1739.Dv ESC 1740or 1741.Sy \&^C 1742characters, has 1743.Sy \&xb , 1744indicating that the 1745.Dq \&f\&1 1746key is used for 1747.Dv ESC 1748and 1749.Dq \&f\&2 1750for ^C. 1751(Only certain Superbees have this problem, depending on the 1752.Tn ROM . ) 1753.Pp 1754Other specific terminal problems may be corrected by adding more 1755capabilities of the form 1756.Sy x Em x . 1757.Ss Similar Terminals 1758If there are two very similar terminals, 1759one can be defined as being just like the other with certain exceptions. 1760The string capability 1761.Sy \&tc 1762can be given 1763with the name of the similar terminal. 1764This capability must be 1765.Em last , 1766and the combined length of the entries 1767must not exceed 1024. 1768The capabilities given before 1769.Sy \&tc 1770override those in the terminal type invoked by 1771.Sy \&tc . 1772A capability can be canceled by placing 1773.Sy \&xx@ 1774to the left of the 1775.Sy \&tc 1776invocation, where 1777.Sy \&xx 1778is the capability. 1779For example, the entry 1780.Bd -literal -offset indent 1781hn\||\|2621\-nl:ks@:ke@:tc=2621: 1782.Ed 1783.Pp 1784defines a 1785.Dq 2621\-nl 1786that does not have the 1787.Sy \&ks 1788or 1789.Sy \&ke 1790capabilities, 1791hence does not turn on the function key labels when in visual mode. 1792This is useful for different modes for a terminal, or for different 1793user preferences. 1794.Sh FILES 1795.Bl -tag -width /usr/share/misc/termcap.db -compact 1796.It Pa /usr/share/misc/termcap 1797File containing terminal descriptions. 1798.It Pa /usr/share/misc/termcap.db 1799Hash database file containing terminal descriptions (see 1800.Xr cap_mkdb 1 ) . 1801.El 1802.Sh SEE ALSO 1803.Xr cap_mkdb 1 , 1804.Xr ex 1 , 1805.Xr more 1 , 1806.Xr tset 1 , 1807.Xr ul 1 , 1808.Xr vi 1 , 1809.Xr curses 3 , 1810.Xr printf 3 , 1811.Xr termcap 3 , 1812.Xr term 5 1813.Sh CAVEATS AND BUGS 1814The 1815.Em Note : 1816.Nm termcap 1817functions 1818were replaced by 1819.Xr terminfo 1820in 1821.At V 1822Release 2.0. 1823The transition will be relatively painless if capabilities flagged as 1824.Dq obsolete 1825are avoided. 1826.Pp 1827Lines and columns are now stored by the kernel as well as in the termcap 1828entry. 1829Most programs now use the kernel information primarily; the information 1830in this file is used only if the kernel does not have any information. 1831.Pp 1832.Xr \&Vi 1833allows only 256 characters for string capabilities, and the routines 1834in 1835.Xr termlib 3 1836do not check for overflow of this buffer. 1837The total length of a single entry (excluding only escaped newlines) 1838may not exceed 1024. 1839.Pp 1840Not all programs support all entries. 1841.Sh HISTORY 1842The 1843.Nm 1844file format appeared in 1845.Bx 3 . 1846