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Manual Pages  — TERMCAP

NAME

termcap – terminal capability data base

CONTENTS

SYNOPSIS


termcap

DESCRIPTION

The termcap file is a data base describing terminals, used, for example, by amp;vi(1) and ncurses(3). Terminals are described in termcap by giving a set of capabilities that they have and by describing how operations are performed. Padding requirements and initialization sequences are included in termcap.

Entries in termcap consist of a number of `:'-separated fields. The first entry for each terminal gives the names that are known for the terminal, separated by `|' characters. The first name given is the most common abbreviation for the terminal. The last name given should be a long name fully identifying the terminal, and all others are understood as synonyms for the terminal name. All names but the last should be in lower case and contain no blanks; the last name may well contain upper case characters and blanks for readability.

Terminal names (except for the last, verbose entry) should be chosen using the following conventions. The particular piece of hardware making up the terminal should have a root name chosen, thus "hp2621" This name should not contain hyphens. Modes that the hardware can be in or user preferences should be indicated by appending a hyphen and an indicator of the mode. Therefore, a "vt100" in 132-column mode would be "vt100-w". The following suffixes should be used where possible: Suffix Ta Meaning - n - amp;np
Example
-wWide mode (more than 80 columns)vt100-w
-amWith automatic margins (usually default)vt100-am
-namWithout automatic marginsvt100-nam
Number of lines on screen aaa-60
-naNo arrow keys (leave them in local)concept100-na
Number of pages of memory concept100-4p
-rvReverse videoconcept100-rv

CAPABILITIES

The description field attempts to convey the semantics of the capability. You may find some codes in the description field:
(P) indicates that padding may be specified.
#[1-9]
  in the description field indicates that the string is passed through tparm(3) or tgoto(3) with parms as given (#i).
(P*) indicates that padding may vary in proportion to the number of lines affected.
(#i) indicates the ith parameter.

These are the boolean capabilities:

Boolean                 TCap    Description
Variables               Code
auto_left_margin        bw      cursor_left wraps from column 0 to last
                                column
auto_right_margin       am      terminal has automatic margins
no_esc_ctlc             xb      beehive (f1=escape, f2=ctrl C)
ceol_standout_glitch    xs      standout not erased by overwriting (hp)
eat_newline_glitch      xn      newline ignored after 80 cols (concept)
erase_overstrike        eo      can erase overstrikes with a blank
generic_type            gn      generic line type
hard_copy               hc      hardcopy terminal
has_meta_key            km      Has a meta key, sets msb high
has_status_line         hs      has extra status line
insert_null_glitch      in      insert mode distinguishes nulls
memory_above            da      display may be retained above the screen
memory_below            db      display may be retained below the screen
move_insert_mode        mi      safe to move while in insert mode
move_standout_mode      ms      safe to move while in standout mode
over_strike             os      terminal can overstrike
status_line_esc_ok      es      escape can be used on the status line
dest_tabs_magic_smso    xt      tabs destructive, magic so char (t1061)
tilde_glitch            hz      cannot print ~'s (hazeltine)
transparent_underline   ul      underline character overstrikes
xon_xoff                xo      terminal uses xon/xoff handshaking
needs_xon_xoff          nx      padding will not work, xon/xoff required
prtr_silent             5i      printer will not echo on screen
hard_cursor             HC      cursor is hard to see
non_rev_rmcup           NR      enter_ca_mode does not reverse exit_ca_mode
no_pad_char             NP      pad character does not exist
non_dest_scroll_region  ND      scrolling region is non-destructive
can_change              cc      terminal can re-define existing colors
back_color_erase        ut      screen erased with background color
hue_lightness_saturation        hl      terminal uses only HLS color
                                        notation (tektronix)
col_addr_glitch         YA      only positive motion for column address and
                                micro_column_address caps
cr_cancels_micro_mode   YB      using cr turns off micro mode
has_print_wheel         YC      printer needs operator to change character
                                set
row_addr_glitch         YD      only positive motion for row_address and
                                micro_row_address caps
semi_auto_right_margin  YE      printing in last column causes cr
cpi_changes_res         YF      changing character pitch changes resolution
lpi_changes_res         YG      changing line pitch changes resolution

These are the numeric capabilities:

Numeric                 TCap    Description
Variables               Code
columns                 co      number of columns in aline
init_tabs               it      tabs initially every # spaces
lines                   li      number of lines on screen or page
lines_of_memory         lm      lines of memory if > line. 0 => varies
magic_cookie_glitch     sg      number of blank chars left by
                                enter_standout_mode or exit_standout_mode
padding_baud_rate       pb      lowest baud rate where padding needed
virtual_terminal        vt      virtual terminal number (CB/unix)
width_status_line       ws      columns in status line
num_labels              Nl      number of labels on screen
label_height            lh      rows in each label
label_width             lw      columns in each label
max_attributes          ma      maximum combined attributes terminal can
                                handle
maximum_windows         MW      maximum number of definable windows
magic_cookie_glitch_ul  ug      number of blanks left by underline
#
# These came in with SVr4's color support
#
max_colors              Co      maximum numbers of colors on screen
max_pairs               pa      maximum number of color-pairs on the screen
no_color_video          NC      video attributes that cannot be used with
                                colors
#
# The following numeric capabilities are present in the SVr4.0 term
# structure, but are not yet documented in the man page.
# They came in with SVr4's printer support.
#
buffer_capacity         Ya      numbers of bytes buffered before printing
dot_vert_spacing        Yb      spacing of pins vertically in pins per inch
dot_horz_spacing        Yc      spacing of dots horizontally in dots per
                                inch
max_micro_address       Yd      maximum value in micro_..._address
max_micro_jump          Ye      maximum value in parm_..._micro
micro_char_size         Yf      character size when in micro mode
micro_line_size         Yg      line size when in micro mode
number_of_pins          Yh      numbers of pins in print-head
output_res_char         Yi      horizontal resolution in units per line
output_res_line         Yj      vertical resolution in units per line
output_res_horz_inch    Yk      horizontal resolution in units per inch
output_res_vert_inch    Yl      vertical resolution in units per inch
print_rate              Ym      print rate in chars per second
wide_char_size          Yn      character step size when in double wide
                                mode
buttons                 BT      number of buttons on mouse
bit_image_entwining     Yo      number of passed for each bit-image row
bit_image_type          Yp      type of bit-image device

These are the string capabilities:

String                  TCap    Description
Variables               Code
back_tab                bt      back tab (P)
bell                    bl      audible signal (bell) (P)
carriage_return         cr      carriage return (P*)
change_scroll_region    cs      change region to line #1 to line #2 (P)
clear_all_tabs          ct      clear all tab stops (P)
clear_screen            cl      clear screen and home cursor (P*)
clr_eol                 ce      clear to end of line (P)
clr_eos                 cd      clear to end of screen (P*)
column_address          ch      horizontal position #1, absolute (P)
command_character       CC      terminal settable cmd character in
                                prototype
cursor_address          cm      move to row #1 columns #2
cursor_down             do      down one line
cursor_home             ho      home cursor
cursor_invisible        vi      make cursor invisible
cursor_left             le      move left one space
cursor_mem_address      CM      memory relative cursor addressing
cursor_normal           ve      make cursor appear normal (undo
                                cursor_invisible/cursor_visible)
cursor_right            nd      move right one space
cursor_to_ll            ll      last line, first column
cursor_up               up      up one line
cursor_visible          vs      make cursor very visible
delete_character        dc      delete character (P*)
delete_line             dl      delete line (P*)
dis_status_line         ds      disable status line
down_half_line          hd      half a line down
enter_alt_charset_mode  as      start alternate character set (P)
enter_blink_mode        mb      turn on blinking
enter_bold_mode         md      turn on bold (extra bright) mode
enter_ca_mode           ti      string to start programs using
                                cursor_address
enter_delete_mode       dm      enter delete mode
enter_dim_mode          mh      turn on half-bright mode
enter_insert_mode       im      enter insert mode
enter_secure_mode       mk      turn on blank mode (characters invisible)
enter_protected_mode    mp      turn on protected mode
enter_reverse_mode      mr      turn on reverse video mode
enter_standout_mode     so      begin standout mode
enter_underline_mode    us      begin underline mode
erase_chars             ec      erase #1 characters (P)
exit_alt_charset_mode   ae      end alternate character set (P)
exit_attribute_mode     me      turn off all attributes
exit_ca_mode            te      strings to end programs using cup
exit_delete_mode        ed      end delete mode
exit_insert_mode        ei      exit insert mode
exit_standout_mode      se      exit standout mode
exit_underline_mode     ue      exit underline mode
flash_screen            vb      visible bell (may not move cursor)
form_feed               ff      hardcopy terminal page eject (P*)
from_status_line        fs      return from status line
init_1string            i1      initialization string
init_2string            is      initialization string
init_3string            i3      initialization string
init_file               if      name of initialization file
insert_character        ic      insert character (P)
insert_line             al      insert line (P*)
insert_padding          ip      insert padding after inserted character
key_backspace           kb      backspace key
key_catab               ka      clear-all-tabs key
key_clear               kC      clear-screen or erase key
key_ctab                kt      clear-tab key
key_dc                  kD      delete-character key
key_dl                  kL      delete-line key
key_down                kd      down-arrow key
key_eic                 kM      sent by rmir or smir in insert mode
key_eol                 kE      clear-to-end-of-line key
key_eos                 kS      clear-to-end-of-screen key
key_f0                  k0      F0 function key
key_f1                  k1      F1 function key
key_f10                 k;      F10 function key
key_f2                  k2      F2 function key
key_f3                  k3      F3 function key
key_f4                  k4      F4 function key
key_f5                  k5      F5 function key
key_f6                  k6      F6 function key
key_f7                  k7      F7 function key
key_f8                  k8      F8 function key
key_f9                  k9      F9 function key
key_home                kh      home key
key_ic                  kI      insert-character key
key_il                  kA      insert-line key
key_left                kl      left-arrow key
key_ll                  kH      last-line key
key_npage               kN      next-page key
key_ppage               kP      prev-page key
key_right               kr      right-arrow key
key_sf                  kF      scroll-forward key
key_sr                  kR      scroll-backward key
key_stab                kT      set-tab key
key_up                  ku      up-arrow key
keypad_local            ke      leave 'keyboard_transmit' mode
keypad_xmit             ks      enter 'keyboard_transmit' mode
lab_f0                  l0      label on function key f0 if not f0
lab_f1                  l1      label on function key f1 if not f1
lab_f10                 la      label on function key f10 if not f10
lab_f2                  l2      label on function key f2 if not f2
lab_f3                  l3      label on function key f3 if not f3
lab_f4                  l4      label on function key f4 if not f4
lab_f5                  l5      label on function key f5 if not f5
lab_f6                  l6      label on function key f6 if not f6
lab_f7                  l7      label on function key f7 if not f7
lab_f8                  l8      label on function key f8 if not f8
lab_f9                  l9      label on function key f9 if not f9
meta_off                mo      turn off meta mode
meta_on                 mm      turn on meta mode (8th-bit on)
newline                 nw      newline (behave like cr followed by lf)
pad_char                pc      padding char (instead of null)
parm_dch                DC      delete #1 chars (P*)
parm_delete_line        DL      delete #1 lines (P*)
parm_down_cursor        DO      down #1 lines (P*)
parm_ich                IC      insert #1 chars (P*)
parm_index              SF      scroll forward #1 lines (P)
parm_insert_line        AL      insert #1 lines (P*)
parm_left_cursor        LE      move #1 chars to the left (P)
parm_right_cursor       RI      move #1 chars to the right (P*)
parm_rindex             SR      scroll back #1 lines (P)
parm_up_cursor          UP      up #1 lines (P*)
pkey_key                pk      program function key #1 to type string #2
pkey_local              pl      program function key #1 to execute
                                string #2
pkey_xmit               px      program function key #1 to transmit
                                string #2
print_screen            ps      print contents of screen
prtr_off                pf      turn off printer
prtr_on                 po      turn on printer
repeat_char             rp      repeat char #1 #2 times (P*)
reset_1string           r1      reset string
reset_2string           r2      reset string
reset_3string           r3      reset string
reset_file              rf      name of reset file
restore_cursor          rc      restore cursor to last position of
                                save_cursor
row_address             cv      vertical position #1 absolute (P)
save_cursor             sc      save current cursor position (P)
scroll_forward          sf      scroll text up (P)
scroll_reverse          sr      scroll text down (P)
set_attributes          sa      define video attributes #1-#9 (PG9)
set_tab                 st      set a tab in every row, current columns
set_window              wi      current window is lines #1-#2 cols #3-#4
tab                     ta      tab to next 8-space hardware tab stop
to_status_line          ts      move to status line
underline_char          uc      underline char and move past it
up_half_line            hu      half a line up
init_prog               iP      path name of program for initialization
key_a1                  K1      upper left of keypad
key_a3                  K3      upper right of keypad
key_b2                  K2      center of keypad
key_c1                  K4      lower left of keypad
key_c3                  K5      lower right of keypad
prtr_non                pO      turn on printer for #1 bytes
termcap_init2           i2      secondary initialization string
termcap_reset           rs      terminal reset string
#
# SVr1 capabilities stop here.  IBM's version of terminfo is the same as
# SVr4 up to this point, but has a different set afterwards.
#
char_padding            rP      like insert_padding but when in insert mode
acs_chars               ac      graphics charset pairs - def=vt100
plab_norm               pn      program label #1 to show string #2
key_btab                kB      back-tab key
enter_xon_mode          SX      turn on xon/xoff handshaking
exit_xon_mode           RX      turn off xon/xoff handshaking
enter_am_mode           SA      turn on automatic margins
exit_am_mode            RA      turn off automatic margins
xon_character           XN      XON character
xoff_character          XF      XOFF character
ena_acs                 eA      enable alternate char set
label_on                LO      turn on soft labels
label_off               LF      turn off soft labels
key_beg                 @1      begin key
key_cancel              @2      cancel key
key_close               @3      close key
key_command             @4      command key
key_copy                @5      copy key
key_create              @6      create key
key_end                 @7      end key
key_enter               @8      enter/send key
key_exit                @9      exit key
key_find                @0      find key
key_help                %1      help key
key_mark                %2      mark key
key_message             %3      message key
key_move                %4      move key
key_next                %5      next key
key_open                %6      open key
key_options             %7      options key
key_previous            %8      previous key
key_print               %9      print key
key_redo                %0      redo key
key_reference           &1      reference key
key_refresh             &2      refresh key
key_replace             &3      replace key
key_restart             &4      restart key
key_resume              &5      resume key
key_save                &6      save key
key_suspend             &7      suspend key
key_undo                &8      undo key
key_sbeg                &9      shifted key
key_scancel             &0      shifted key
key_scommand            *1      shifted key
key_scopy               *2      shifted key
key_screate             *3      shifted key
key_sdc                 *4      shifted key
key_sdl                 *5      shifted key
key_select              *6      select key
key_send                *7      shifted key
key_seol                *8      shifted key
key_sexit               *9      shifted key
key_sfind               *0      shifted key
key_shelp               #1      shifted key
key_shome               #2      shifted key
key_sic                 #3      shifted key
key_sleft               #4      shifted key
key_smessage            %a      shifted key
key_smove               %b      shifted key
key_snext               %c      shifted key
key_soptions            %d      shifted key
key_sprevious           %e      shifted key
key_sprint              %f      shifted key
key_sredo               %g      shifted key
key_sreplace            %h      shifted key
key_sright              %i      shifted key
key_srsume              %j      shifted key
key_ssave               !1      shifted key
key_ssuspend            !2      shifted key
key_sundo               !3      shifted key
req_for_input           RF      send next input char (for ptys)
key_f11                 F1      F11 function key
key_f12                 F2      F12 function key
key_f13                 F3      F13 function key
key_f14                 F4      F14 function key
key_f15                 F5      F15 function key
key_f16                 F6      F16 function key
key_f17                 F7      F17 function key
key_f18                 F8      F18 function key
key_f19                 F9      F19 function key
key_f20                 FA      F20 function key
key_f21                 FB      F21 function key
key_f22                 FC      F22 function key
key_f23                 FD      F23 function key
key_f24                 FE      F24 function key
key_f25                 FF      F25 function key
key_f26                 FG      F26 function key
key_f27                 FH      F27 function key
key_f28                 FI      F28 function key
key_f29                 FJ      F29 function key
key_f30                 FK      F30 function key
key_f31                 FL      F31 function key
key_f32                 FM      F32 function key
key_f33                 FN      F33 function key
key_f34                 FO      F34 function key
key_f35                 FP      F35 function key
key_f36                 FQ      F36 function key
key_f37                 FR      F37 function key
key_f38                 FS      F38 function key
key_f39                 FT      F39 function key
key_f40                 FU      F40 function key
key_f41                 FV      F41 function key
key_f42                 FW      F42 function key
key_f43                 FX      F43 function key
key_f44                 FY      F44 function key
key_f45                 FZ      F45 function key
key_f46                 Fa      F46 function key
key_f47                 Fb      F47 function key
key_f48                 Fc      F48 function key
key_f49                 Fd      F49 function key
key_f50                 Fe      F50 function key
key_f51                 Ff      F51 function key
key_f52                 Fg      F52 function key
key_f53                 Fh      F53 function key
key_f54                 Fi      F54 function key
key_f55                 Fj      F55 function key
key_f56                 Fk      F56 function key
key_f57                 Fl      F57 function key
key_f58                 Fm      F58 function key
key_f59                 Fn      F59 function key
key_f60                 Fo      F60 function key
key_f61                 Fp      F61 function key
key_f62                 Fq      F62 function key
key_f63                 Fr      F63 function key
clr_bol                 cb      Clear to beginning of line
clear_margins           MC      clear right and left soft margins
set_left_margin         ML      set left soft margin
set_right_margin        MR      set right soft margin
label_format            Lf      label format
set_clock               SC      set clock, #1 hrs #2 mins #3 secs
display_clock           DK      display clock at (#1,#2)
remove_clock            RC      remove clock
create_window           CW      define a window #1 from #2, #3 to #4, #5
goto_window             WG      go to window #1
hangup                  HU      hang-up phone
dial_phone              DI      dial number #1
quick_dial              QD      dial number #1 without checking
tone                    TO      select touch tone dialing
pulse                   PU      select pulse dialling
flash_hook              fh      flash switch hook
fixed_pause             PA      pause for 2-3 seconds
wait_tone               WA      wait for dial-tone
user0                   u0      User string #0
user1                   u1      User string #1
user2                   u2      User string #2
user3                   u3      User string #3
user4                   u4      User string #4
user5                   u5      User string #5
user6                   u6      User string #6
user7                   u7      User string #7
user8                   u8      User string #8
user9                   u9      User string #9
#
# SVr4 added these capabilities to support color
#
orig_pair               op      Set default pair to its original value
orig_colors             oc      Set all color pairs to the original ones
initialize_color        Ic      initialize color #1 to (#2,#3,#4)
initialize_pair         Ip      Initialize color pair #1 to fg=(#2,#3,#4),
                                bg=(#5,#6,#7)
set_color_pair          sp      Set current color pair to #1
set_foreground          Sf      Set foreground color #1
set_background          Sb      Set background color #1
#
# SVr4 added these capabilities to support printers
#
change_char_pitch       ZA      Change number of characters per inch
change_line_pitch       ZB      Change number of lines per inch
change_res_horz         ZC      Change horizontal resolution
change_res_vert         ZD      Change vertical resolution
define_char             ZE      Define a character
enter_doublewide_mode   ZF      Enter double-wide mode
enter_draft_quality     ZG      Enter draft-quality mode
enter_italics_mode      ZH      Enter italic mode
enter_leftward_mode     ZI      Start leftward carriage motion
enter_micro_mode        ZJ      Start micro-motion mode
enter_near_letter_quality       ZK      Enter NLQ mode
enter_normal_quality    ZL      Enter normal-quality mode
enter_shadow_mode       ZM      Enter shadow-print mode
enter_subscript_mode    ZN      Enter subscript mode
enter_superscript_mode  ZO      Enter superscript mode
enter_upward_mode       ZP      Start upward carriage motion
exit_doublewide_mode    ZQ      End double-wide mode
exit_italics_mode       ZR      End italic mode
exit_leftward_mode      ZS      End left-motion mode
exit_micro_mode         ZT      End micro-motion mode
exit_shadow_mode        ZU      End shadow-print mode
exit_subscript_mode     ZV      End subscript mode
exit_superscript_mode   ZW      End superscript mode
exit_upward_mode        ZX      End reverse character motion
micro_column_address    ZY      Like column_address in micro mode
micro_down              ZZ      Like cursor_down in micro mode
micro_left              Za      Like cursor_left in micro mode
micro_right             Zb      Like cursor_right in micro mode
micro_row_address       Zc      Like row_address in micro mode
micro_up                Zd      Like cursor_up in micro mode
order_of_pins           Ze      Match software bits to print-head pins
parm_down_micro         Zf      Like parm_down_cursor in micro mode
parm_left_micro         Zg      Like parm_left_cursor in micro mode
parm_right_micro        Zh      Like parm_right_cursor in micro mode
parm_up_micro           Zi      Like parm_up_cursor in micro mode
select_char_set         Zj      Select character set
set_bottom_margin       Zk      Set bottom margin at current line
set_bottom_margin_parm  Zl      Set bottom margin at line #1 or #2 lines
                                from bottom
set_left_margin_parm    Zm      Set left (right) margin at column #1 (#2)
set_right_margin_parm   Zn      Set right margin at column #1
set_top_margin          Zo      Set top margin at current line
set_top_margin_parm     Zp      Set top (bottom) margin at row #1 (#2)
start_bit_image         Zq      Start printing bit image graphics
start_char_set_def      Zr      Start character set definition
stop_bit_image          Zs      Stop printing bit image graphics
stop_char_set_def       Zt      End definition of character aet
subscript_characters    Zu      List of subscriptible characters
superscript_characters  Zv      List of superscriptible characters
these_cause_cr          Zw      Printing any of these chars causes CR
zero_motion             Zx      No motion for subsequent character
#
# The following string capabilities are present in the SVr4.0 term
# structure, but are not documented in the man page.
#
char_set_names          Zy      List of character set names
key_mouse               Km      Mouse event has occurred
mouse_info              Mi      Mouse status information
req_mouse_pos           RQ      Request mouse position
get_mouse               Gm      Curses should get button events
set_a_foreground        AF      Set ANSI foreground color
set_a_background        AB      Set ANSI background color
pkey_plab               xl      Program function key #1 to type string #2
                                and show string #3
device_type             dv      Indicate language/codeset support
code_set_init           ci      Init sequence for multiple codesets
set0_des_seq            s0      Shift to code set 0 (EUC set 0, ASCII)
set1_des_seq            s1      Shift to code set 1
set2_des_seq            s2      Shift to code set 2
set3_des_seq            s3      Shift to code set 3
set_lr_margin           ML      Set both left and right margins to #1, #2
set_tb_margin           MT      Sets both top and bottom margins to #1, #2
bit_image_repeat        Xy      Repeat bit image cell #1 #2 times
bit_image_newline       Zz      Move to next row of the bit image
bit_image_carriage_return       Yv      Move to beginning of same row
color_names             Yw      Give name for color #1
define_bit_image_region Yx      Define rectangular bit image region
end_bit_image_region    Yy      End a bit-image region
set_color_band          Yz      Change to ribbon color #1
set_page_length         YZ      Set page length to #1 lines
#
# SVr4 added these capabilities for direct PC-clone support
#
display_pc_char         S1      Display PC character
enter_pc_charset_mode   S2      Enter PC character display mode
exit_pc_charset_mode    S3      Exit PC character display mode
enter_scancode_mode     S4      Enter PC scancode mode
exit_scancode_mode      S5      Exit PC scancode mode
pc_term_options         S6      PC terminal options
scancode_escape         S7      Escape for scancode emulation
alt_scancode_esc        S8      Alternate escape for scancode emulation
#
# The XSI Curses standard added these.
#
enter_horizontal_hl_mode        Xh      Enter horizontal highlight mode
enter_left_hl_mode      Xl      Enter left highlight mode
enter_low_hl_mode       Xo      Enter low highlight mode
enter_right_hl_mode     Xr      Enter right highlight mode
enter_top_hl_mode       Xt      Enter top highlight mode
enter_vertical_hl_mode  Xv      Enter vertical highlight mode

Obsolete termcap capabilities. New software should not rely on them at all.

Boolean                 TCap    Description
Variables               Code
linefeed_is_newline     NL      move down with ^J
even_parity             EP      terminal requires even parity
odd_parity              OP      terminal requires odd parity
half_duplex             HD      terminal is half-duplex
lower_case_only         LC      terminal has only lower case
upper_case_only         UC      terminal has only upper case
has_hardware_tabs       pt      has 8-char tabs invoked with ^I
return_does_clr_eol     xr      return clears the line
tek_4025_insert_line    xx      Tektronix 4025 insert-line glitch
backspaces_with_bs      bs      uses ^H to move left
crt_no_scrolling        ns      crt cannot scroll
no_correctly_working_cr nc      no way to go to start of line
Number                  TCap    Description
Variables               Code
backspace_delay         dB      padding required for ^H
form_feed_delay         dF      padding required for ^L
horizontal_tab_delay    dT      padding required for ^I
vertical_tab_delay      dV      padding required for ^V
number_of_function_keys kn      count of function keys
carriage_return_delay   dC      pad needed for CR
new_line_delay          dN      pad needed for LF
String                  TCap    Description
Variables               Code
other_non_function_keys ko      list of self-mapped keycaps
arrow_key_map           ma      map arrow keys
memory_lock_above       ml      lock visible screen memory above the
                                current line
memory_unlock           mu      unlock visible screen memory above the
                                current line
linefeed_if_not_lf      nl      use to move down
backspace_if_not_bs     bc      move left, if not ^H

A Sample Entry

The following entry, which describes the Concept-100, is among the more complex entries in the termcap file as of this writing.
ca|concept100|c100|concept|c104|concept100-4p|HDS Concept-100:\
        :al=3*\E^R:am:bl=^G:cd=16*\E^C:ce=16\E^U:cl=2*^L:cm=\Ea%+ %+ :\
        :co#80:.cr=9^M:db:dc=16\E^A:dl=3*\E^B:do=^J:ei=\E\200:eo:im=\E^P:in:\
        :ip=16*:is=\EU\Ef\E7\E5\E8\El\ENH\EK\E\200\Eo&\200\Eo\47\E:k1=\E5:\
        :k2=\E6:k3=\E7:kb=^h:kd=\E<:ke=\Ex:kh=\E?:kl=\E>:kr=\E=:ks=\EX:\
        :ku=\E;:le=^H:li#24:mb=\EC:me=\EN\200:mh=\EE:mi:mk=\EH:mp=\EI:\
        :mr=\ED:nd=\E=:pb#9600:rp=0.2*\Er%.%+ :se=\Ed\Ee:sf=^J:so=\EE\ED:\
        :.ta=8\t:te=\Ev    \200\200\200\200\200\200\Ep\r\n:\
        :ti=\EU\Ev  8p\Ep\r:ue=\Eg:ul:up=\E;:us=\EG:\
        :vb=\Ek\200\200\200\200\200\200\200\200\200\200\200\200\200\200\EK:\
        :ve=\Ew:vs=\EW:vt#8:xn:\
        :bs:cr=^M:dC#9:dT#8:nl=^J:ta=^I:pt:

Entries may continue onto multiple lines by giving a \ as the last character of a line, and empty fields may be included for readability (here between the last field on a line and the first field on the next). Comments may be included on lines beginning with "#".

Types of Capabilities

Capabilities in termcap are of three types: Boolean capabilities, which indicate particular features that the terminal has; numeric capabilities, giving the size of the display or the size of other attributes; and string capabilities, which give character sequences that can be used to perform particular terminal operations. All capabilities have two-letter codes. For instance, the fact that the Concept has automatic margins (an automatic return and linefeed when the end of a line is reached) is indicated by the Boolean capability amp;am. Hence the description of the Concept includes amp;am.

Numeric capabilities are followed by the character `#' then the value. In the example above amp;co, which indicates the number of columns the display has, gives the value `80' for the Concept.

Finally, string-valued capabilities, such as amp;ce (clear-to-end-of-line sequence) are given by the two-letter code, an `=', then a string ending at the next following `:'. A delay in milliseconds may appear after the `=' in such a capability, which causes padding characters to be supplied by tputs(3) after the remainder of the string is sent to provide this delay. The delay can be either a number, such as `20', or a number followed by an `*', such as `3*'. An `*' indicates that the padding required is proportional to the number of lines affected by the operation, and the amount given is the per-affected-line padding required. (In the case of insert-character, the factor is still the number of lines affected; this is always 1 unless the terminal has amp;in and the software uses it.) When an `*' is specified, it is sometimes useful to give a delay of the form `3.5' to specify a delay per line to tenths of milliseconds. (Only one decimal place is allowed.)

A number of escape sequences are provided in the string-valued capabilities for easy encoding of control characters there. amp;\E maps to an ESC character, amp;^X maps to a control-X for any appropriate X, and the sequences amp;\n amp;\r amp;\t amp;\b amp;\f map to linefeed, return, tab, backspace, and formfeed, respectively. Finally, characters may be given as three octal digits after a amp;\, and the characters amp;^ and amp;\ may be given as amp;\^ and amp;\\. If it is necessary to place a amp;: in a capability it must be escaped as \: or be encoded as amp;\072. If it is necessary to place a NUL character in a string capability it must be encoded as amp;\200. (The routines that deal with termcap use C strings and strip the high bits of the output very late, so that a amp;\200 comes out as a amp;\000 would.)

Sometimes individual capabilities must be commented out. To do this, put a period before the capability name. For example, see the first amp;cr and amp;ta in the example above.

Preparing Descriptions

The most effective way to prepare a terminal description is by imitating the description of a similar terminal in termcap and to build up a description gradually, using partial descriptions with amp;vi(1) to check that they are correct. Be aware that a very unusual terminal may expose deficiencies in the ability of the termcap file to describe it or bugs in amp;vi(1). To easily test a new terminal description you are working on you can put it in your home directory in a file called .termcap and programs will look there before looking in /usr/share/misc/termcap. You can also set the environment variable TERMPATH to a list of absolute file pathnames (separated by spaces or colons), one of which contains the description you are working on, and programs will search them in the order listed, and nowhere else. See termcap(3). The TERMCAP environment variable is usually set to the termcap entry itself to avoid reading files when starting up a program.

To get the padding for insert-line right (if the terminal manufacturer did not document it), a severe test is to use amp;vi(1) to edit /etc/passwd at 9600 baud, delete roughly 16 lines from the middle of the screen, then hit the `u' key several times quickly. If the display messes up, more padding is usually needed. A similar test can be used for insert-character.

Basic Capabilities

The number of columns on each line of the display is given by the amp;co numeric capability. If the display is a CRT, then the number of lines on the screen is given by the amp;li capability. If the display wraps around to the beginning of the next line when the cursor reaches the right margin, then it should have the amp;am capability. If the terminal can clear its screen, the code to do this is given by the amp;cl string capability. If the terminal overstrikes (rather than clearing the position when a character is overwritten), it should have the amp;os capability. If the terminal is a printing terminal, with no soft copy unit, give it both amp;hc and amp;os. ( amp;os applies to storage scope terminals, such as the Tektronix 4010 series, as well as to hard copy and APL terminals.) If there is a code to move the cursor to the left edge of the current row, give this as amp;cr. (Normally this will be carriage-return, amp;^M.) If there is a code to produce an audible signal (bell, beep, etc.), give this as amp;bl.

If there is a code (such as backspace) to move the cursor one position to the left, that capability should be given as amp;le. Similarly, codes to move to the right, up, and down should be given as amp;nd, amp;up, and amp;do, respectively. These local cursor motions should not alter the text they pass over; for example, you would not normally use "nd= amp;" unless the terminal has the amp;os capability, because the space would erase the character moved over.

A very important point here is that the local cursor motions encoded in termcap have undefined behavior at the left and top edges of a CRT display. Programs should never attempt to backspace around the left edge, unless amp;bw is given, and never attempt to go up off the top using local cursor motions.

In order to scroll text up, a program goes to the bottom left corner of the screen and sends the amp;sf (index) string. To scroll text down, a program goes to the top left corner of the screen and sends the amp;sr (reverse index) string. The strings amp;sf and amp;sr have undefined behavior when not on their respective corners of the screen. Parameterized versions of the scrolling sequences are amp;SF and amp;SR, which have the same semantics as amp;sf and amp;sr except that they take one parameter and scroll that many lines. They also have undefined behavior except at the appropriate corner of the screen.

The amp;am capability tells whether the cursor sticks at the right edge of the screen when text is output there, but this does not necessarily apply to amp;nd from the last column. Leftward local motion is defined from the left edge only when amp;bw is given; then an amp;le from the left edge will move to the right edge of the previous row. This is useful for drawing a box around the edge of the screen, for example. If the terminal has switch-selectable automatic margins, the termcap description usually assumes that this feature is on, i.e., amp;am. If the terminal has a command that moves to the first column of the next line, that command can be given as amp;nw (newline). It is permissible for this to clear the remainder of the current line, so if the terminal has no correctly-working amp;CR and amp;LF it may still be possible to craft a working amp;nw out of one or both of them.

These capabilities suffice to describe hardcopy and "glass-tty" terminals. Thus the Teletype model 33 is described as

T3|tty33|33|tty|Teletype model 33:\
        :bl=^G:co#72:cr=^M:do=^J:hc:os:

and the Lear Siegler ADM-3 is described as

l3|adm3|3|LSI ADM-3:\
:am:bl=^G:cl=^Z:co#80:cr=^M:do=^J:le=^H:li#24:sf=^J:

Parameterized Strings

Cursor addressing and other strings requiring parameters are described by a parameterized string capability, with printf(3)-like escapes amp;%x in it, while other characters are passed through unchanged. For example, to address the cursor the amp;cm capability is given, using two parameters: the row and column to move to. (Rows and columns are numbered from zero and refer to the physical screen visible to the user, not to any unseen memory. If the terminal has memory-relative cursor addressing, that can be indicated by an analogous amp;CM capability.)

The amp;% encodings have the following meanings:

%%
output `%'

%d
output value as inprintf(3) %d

%2
output value as inprintf(3) %2d

%3
output value as inprintf(3) %3d

%.
output value as inprintf(3) %c

%+ x
add x to value, then do %.

%> amp;xy
ifvalue > x then add y, no output

%r
reverse order of two parameters, no output

%i
increment by one, no output

%n
exclusive-or all parameters with 0140 (Datamedia 2500)

amp;%B
BCD (16*(value/10)) + (value%10), no output
Ta Reverse coding (value - 2*(value%16)), no output (Delta Data).

Consider the Hewlett-Packard 2645, which, to get to row 3 and column 12, needs to be sent "\E&a12c03Y" padded for 6 milliseconds. Note that the order of the row and column coordinates is reversed here and that the row and column are sent as two-digit integers. Thus its amp;cm capability is "cm=6\E&%r%2c%2Y".

The Datamedia 2500 needs the current row and column sent encoded in binary using "amp;%.". Terminals that use "%.amp;" need to be able to backspace the cursor ( amp;le) and to move the cursor up one line on the screen ( amp;up). This is necessary because it is not always safe to transmit amp;\n, amp;^D, and amp;\r, as the system may change or discard them. (Programs using termcap must set terminal modes so that tabs are not expanded, so amp;\t is safe to send. This turns out to be essential for the Ann Arbor 4080.)

A final example is the Lear Siegler ADM-3a, which offsets row and column by a blank character, thus "cm=\E=%+ %+ amp;".

Row or column absolute cursor addressing can be given as single parameter capabilities amp;ch (horizontal position absolute) and amp;cv (vertical position absolute). Sometimes these are shorter than the more general two-parameter sequence (as with the Hewlett-Packard 2645) and can be used in preference to amp;cm. If there are parameterized local motions ( e.g., move n positions to the right) these can be given as amp;DO, amp;LE, amp;RI, and amp;UP with a single parameter indicating how many positions to move. These are primarily useful if the terminal does not have amp;cm, such as the Tektronix 4025.

Cursor Motions

If the terminal has a fast way to home the cursor (to the very upper left corner of the screen), this can be given as amp;ho. Similarly, a fast way of getting to the lower left-hand corner can be given as amp;ll; this may involve going up with amp;up from the home position, but a program should never do this itself (unless amp;ll does), because it can make no assumption about the effect of moving up from the home position. Note that the home position is the same as cursor address (0,0): to the top left corner of the screen, not of memory. (Therefore, the "\EH" sequence on Hewlett-Packard terminals cannot be used for amp;ho.)

Area Clears

If the terminal can clear from the current position to the end of the line, leaving the cursor where it is, this should be given as amp;ce. If the terminal can clear from the current position to the end of the display, this should be given as amp;cd. amp;cd must only be invoked from the first column of a line. (Therefore, it can be simulated by a request to delete a large number of lines, if a true amp;cd is not available.)

Insert/Delete Line

If the terminal can open a new blank line before the line containing the cursor, this should be given as amp;al; this must be invoked only from the first position of a line. The cursor must then appear at the left of the newly blank line. If the terminal can delete the line that the cursor is on, this should be given as amp;dl; this must only be used from the first position on the line to be deleted. Versions of amp;al and amp;dl which take a single parameter and insert or delete that many lines can be given as amp;AL and amp;DL. If the terminal has a settable scrolling region (like the VT100), the command to set this can be described with the amp;cs capability, which takes two parameters: the top and bottom lines of the scrolling region. The cursor position is, alas, undefined after using this command. It is possible to get the effect of insert or delete line using this command &#151; the amp;sc and amp;rc (save and restore cursor) commands are also useful. Inserting lines at the top or bottom of the screen can also be done using amp;sr or amp;sf on many terminals without a true insert/delete line, and is often faster even on terminals with those features.

If the terminal has the ability to define a window as part of memory which all commands affect, it should be given as the parameterized string amp;wi. The four parameters are the starting and ending lines in memory and the starting and ending columns in memory, in that order. (This terminfo(5) capability is described for completeness. It is unlikely that any Ns program will support it.)

If the terminal can retain display memory above the screen, then the amp;da capability should be given; if display memory can be retained below, then amp;db should be given. These indicate that deleting a line or scrolling may bring non-blank lines up from below or that scrolling back with amp;sr may bring down non-blank lines.

Insert/Delete Character

There are two basic kinds of intelligent terminals with respect to insert/delete character that can be described using termcap. The most common insert/delete character operations affect only the characters on the current line and shift characters off the end of the line rigidly. Other terminals, such as the Concept-100 and the Perkin Elmer Owl, make a distinction between typed and untyped blanks on the screen, shifting upon an insert or delete only to an untyped blank on the screen which is either eliminated or expanded to two untyped blanks. You can determine the kind of terminal you have by clearing the screen then typing text separated by cursor motions. Type "abc def" using local cursor motions (not spaces) between the "abc" and the "def". Then position the cursor before the "abc" and put the terminal in insert mode. If typing characters causes the rest of the line to shift rigidly and characters to fall off the end, then your terminal does not distinguish between blanks and untyped positions. If the "abc" shifts over to the "def" which then move together around the end of the current line and onto the next as you insert, then you have the second type of terminal and should give the capability amp;in, which stands for "insert null". While these are two logically separate attributes (one line amp;vs. multi-line insert mode, and special treatment of untyped spaces), we have seen no terminals whose insert mode cannot be described with the single attribute.

The termcap entries can describe both terminals that have an insert mode and terminals that send a simple sequence to open a blank position on the current line. Give as amp;im the sequence to get into insert mode. Give as amp;ei the sequence to leave insert mode. Now give as amp;ic any sequence that needs to be sent just before each character to be inserted. Most terminals with a true insert mode will not give amp;ic; terminals that use a sequence to open a screen position should give it here. (If your terminal has both, insert mode is usually preferable to amp;ic. Do not give both unless the terminal actually requires both to be used in combination.) If post-insert padding is needed, give this as a number of milliseconds in amp;ip (a string option). Any other sequence that may need to be sent after insertion of a single character can also be given in amp;ip. If your terminal needs to be placed into an `insert mode' and needs a special code preceding each inserted character, then both amp;im/ amp;ei and amp;ic can be given, and both will be used. The amp;IC capability, with one parameter n, will repeat the effects of amp;ic n times.

It is occasionally necessary to move around while in insert mode to delete characters on the same line ( e.g., if there is a tab after the insertion position). If your terminal allows motion while in insert mode, you can give the capability amp;mi to speed up inserting in this case. Omitting amp;mi will affect only speed. Some terminals (notably Datamedia's) must not have amp;mi because of the way their insert mode works.

Finally, you can specify amp;dc to delete a single character, amp;DC with one parameter n to delete n characters, and delete mode by giving amp;dm and amp;ed to enter and exit delete mode (which is any mode the terminal needs to be placed in for amp;dc to work).

Highlighting, Underlining, and Visible Bells

If your terminal has one or more kinds of display attributes, these can be represented in a number of different ways. You should choose one display form as standout mode, representing a good high-contrast, easy-on-the-eyes format for highlighting error messages and other attention getters. (If you have a choice, reverse video plus half-bright is good, or reverse video alone.) The sequences to enter and exit standout mode are given as amp;so and amp;se, respectively. If the code to change into or out of standout mode leaves one or even two blank spaces or garbage characters on the screen, as the TVI 912 and Teleray 1061 do, then amp;sg should be given to tell how many characters are left.

Codes to begin underlining and end underlining can be given as amp;us and amp;ue, respectively. Underline mode change garbage is specified by amp;ug, similar to amp;sg. If the terminal has a code to underline the current character and move the cursor one position to the right, such as the Microterm Mime, this can be given as amp;uc.

Other capabilities to enter various highlighting modes include amp;mb (blinking), amp;md (bold or extra bright), amp;mh (dim or half-bright), amp;mk (blanking or invisible text), amp;mp (protected), amp;mr (reverse video), amp;me (turn off all attribute modes), amp;as (enter alternate character set mode), and amp;ae (exit alternate character set mode). Turning on any of these modes singly may or may not turn off other modes.

If there is a sequence to set arbitrary combinations of mode, this should be given as amp;sa (set attributes), taking 9 parameters. Each parameter is either 0 or 1, as the corresponding attributes is on or off. The 9 parameters are, in order: standout, underline, reverse, blink, dim, bold, blank, protect, and alternate character set. Not all modes need be supported by amp;sa, only those for which corresponding attribute commands exist. (It is unlikely that a Ns program will support this capability, which is defined for compatibility with terminfo(5).)

Terminals with the "magic cookie" glitches ( amp;sg and amp;ug), rather than maintaining extra attribute bits for each character cell, instead deposit special "cookies", or "garbage characters", when they receive mode-setting sequences, which affect the display algorithm.

Some terminals, such as the Hewlett-Packard 2621, automatically leave standout mode when they move to a new line or when the cursor is addressed. Programs using standout mode should exit standout mode on such terminals before moving the cursor or sending a newline. On terminals where this is not a problem, the amp;ms capability should be present to say that this overhead is unnecessary.

If the terminal has a way of flashing the screen to indicate an error quietly (a bell replacement), this can be given as amp;vb; it must not move the cursor.

If the cursor needs to be made more visible than normal when it is not on the bottom line (to change, for example, a non-blinking underline into an easier-to-find block or blinking underline), give this sequence as amp;vs. If there is a way to make the cursor completely invisible, give that as amp;vi. The capability amp;ve, which undoes the effects of both of these modes, should also be given.

If your terminal correctly displays underlined characters (with no special codes needed) even though it does not overstrike, then you should give the capability amp;ul. If overstrikes are erasable with a blank, this should be indicated by giving amp;eo.

Keypad

If the terminal has a keypad that transmits codes when the keys are pressed, this information can be given. Note that it is not possible to handle terminals where the keypad only works in local mode (this applies, for example, to the unshifted Hewlett-Packard 2621 keys). If the keypad can be set to transmit or not transmit, give these codes as amp;ks and amp;ke. Otherwise the keypad is assumed to always transmit. The codes sent by the left-arrow, right-arrow, up-arrow, down-arrow, and home keys can be given as amp;kl, amp;kr, amp;ku, amp;kd, and amp;kh, respectively. If there are function keys such as f0, f1, ..., f9, the codes they send can be given as amp;k0, amp;k1, amp;..., amp;k9. If these keys have labels other than the default f0 through f9, the labels can be given as amp;l0, amp;l1, amp;..., amp;l9. The codes transmitted by certain other special keys can be given: amp;kH (home down), amp;kb (backspace), amp;ka (clear all tabs), amp;kt (clear the tab stop in this column), amp;kC (clear screen or erase), amp;kD (delete character), amp;kL (delete line), amp;kM (exit insert mode), amp;kE (clear to end of line), amp;kS (clear to end of screen), amp;kI (insert character or enter insert mode), amp;kA (insert line), amp;kN (next page), amp;kP (previous page), amp;kF (scroll forward/down), amp;kR (scroll backward/up), and amp;kT (set a tab stop in this column). In addition, if the keypad has a 3 by 3 array of keys including the four arrow keys, then the other five keys can be given as amp;K1, amp;K2, amp;K3, amp;K4, and amp;K5. These keys are useful when the effects of a 3 by 3 directional pad are needed. The obsolete amp;ko capability formerly used to describe "other" function keys has been completely supplanted by the above capabilities.

The amp;ma entry is also used to indicate arrow keys on terminals that have single-character arrow keys. It is obsolete but still in use in version 2 of amp;vi which must be run on some minicomputers due to memory limitations. This field is redundant with amp;kl, amp;kr, amp;ku, amp;kd, and amp;kh. It consists of groups of two characters. In each group, the first character is what an arrow key sends, and the second character is the corresponding amp;vi command. These commands are h for amp;kl, j for amp;kd, k for amp;ku, l for amp;kr, and H for amp;kh. For example, the Mime would have "ma=^Hh^Kj^Zk^Xl" indicating arrow keys left (^H), down (^K), up (^Z), and right (^X). (There is no home key on the Mime.)

Tabs and Initialization

If the terminal needs to be in a special mode when running a program that uses these capabilities, the codes to enter and exit this mode can be given as amp;ti and amp;te. This arises, for example, from terminals like the Concept with more than one page of memory. If the terminal has only memory-relative cursor addressing and not screen-relative cursor addressing, a screen-sized window must be fixed into the display for cursor addressing to work properly. This is also used for the Tektronix 4025, where amp;ti sets the command character to be the one used by termcap.

Other capabilities include amp;is, an initialization string for the terminal, and amp;if, the name of a file containing long initialization strings. These strings are expected to set the terminal into modes consistent with the rest of the termcap description. They are normally sent to the terminal by the tset(1) program each time the user logs in. They will be printed in the following order: amp;is; setting tabs using amp;ct and amp;st; and finally amp;if. (Terminfo uses amp;iamp;1-i2 instead of amp;is and runs the program amp;iP and prints amp;iamp;3 after the other initializations.) A pair of sequences that does a harder reset from a totally unknown state can be analogously given as amp;rs and amp;if. These strings are output by the reset(1) program, which is used when the terminal gets into a wedged state. (Terminfo uses amp;r1-r3 instead of amp;rs.) Commands are normally placed in amp;rs and amp;rf only if they produce annoying effects on the screen and are not necessary when logging in. For example, the command to set the VT100 into 80-column mode would normally be part of amp;is, but it causes an annoying glitch of the screen and is not normally needed since the terminal is usually already in 80-column mode.

If the terminal has hardware tabs, the command to advance to the next tab stop can be given as amp;ta (usually amp;^I). A "backtab" command which moves leftward to the previous tab stop can be given as amp;bt. By convention, if the terminal driver modes indicate that tab stops are being expanded by the computer rather than being sent to the terminal, programs should not use amp;ta or amp;bt even if they are present, since the user may not have the tab stops properly set. If the terminal has hardware tabs that are initially set every n positions when the terminal is powered up, then the numeric parameter amp;it is given, showing the number of positions between tab stops. This is normally used by the tset(1) command to determine whether to set the driver mode for hardware tab expansion, and whether to set the tab stops. If the terminal has tab stops that can be saved in nonvolatile memory, the termcap description can assume that they are properly set.

If there are commands to set and clear tab stops, they can be given as amp;ct (clear all tab stops) and amp;st (set a tab stop in the current column of every row). If a more complex sequence is needed to set the tabs than can be described by this, the sequence can be placed in amp;is or amp;if.

Delays

Certain capabilities control padding in the terminal driver. These are primarily needed by hardcopy terminals and are used by the tset(1) program to set terminal driver modes appropriately. Delays embedded in the capabilities amp;cr, amp;sf, amp;le, amp;ff, and amp;ta will cause the appropriate delay bits to be set in the terminal driver. If amp;pb (padding baud rate) is given, these values can be ignored at baud rates below the value of amp;pb. For BSD 4.2 tset(1), the delays are given as numeric capabilities amp;dC, amp;dN, amp;dB, amp;dF, and amp;dT instead.

Miscellaneous

If the terminal requires other than a NUL (zero) character as a pad, this can be given as amp;pc. Only the first character of the amp;pc string is used.

If the terminal has commands to save and restore the position of the cursor, give them as amp;sc and amp;rc.

If the terminal has an extra "status line" that is not normally used by software, this fact can be indicated. If the status line is viewed as an extra line below the bottom line, then the capability amp;hs should be given. Special strings to go to a position in the status line and to return from the status line can be given as amp;ts and amp;fs. ( amp;fs must leave the cursor position in the same place that it was before amp;ts. If necessary, the amp;sc and amp;rc strings can be included in amp;ts and amp;fs to get this effect.) The capability amp;ts takes one parameter, which is the column number of the status line to which the cursor is to be moved. If escape sequences and other special commands such as tab work while in the status line, the flag amp;es can be given. A string that turns off the status line (or otherwise erases its contents) should be given as amp;ds. The status line is normally assumed to be the same width as the rest of the screen, i.e., amp;co. If the status line is a different width (possibly because the terminal does not allow an entire line to be loaded), then its width in columns can be indicated with the numeric parameter amp;ws.

If the terminal can move up or down half a line, this can be indicated with amp;hu (half-line up) and amp;hd (half-line down). This is primarily useful for superscripts and subscripts on hardcopy terminals. If a hardcopy terminal can eject to the next page (form feed), give this as amp;ff (usually amp;^L).

If there is a command to repeat a given character a given number of times (to save time transmitting a large number of identical characters), this can be indicated with the parameterized string amp;rp. The first parameter is the character to be repeated and the second is the number of times to repeat it. (This is a terminfo(5) feature that is unlikely to be supported by a program that uses termcap.)

If the terminal has a settable command character, such as the Tektronix 4025, this can be indicated with amp;CC. A prototype command character is chosen which is used in all capabilities. This character is given in the amp;CC capability to identify it. The following convention is supported on some Unix systems: The environment is to be searched for a amp;CC variable, and if found, all occurrences of the prototype character are replaced by the character in the environment variable. This use of the amp;CC environment variable is a very bad idea, as it conflicts with make(1).

Terminal descriptions that do not represent a specific kind of known terminal, such as switch, dialup, patch, and network, should include the amp;gn (generic) capability so that programs can complain that they do not know how to talk to the terminal. (This capability does not apply to virtual terminal descriptions for which the escape sequences are known.)

If the terminal uses xoff/xon ( DC3/ DC1) handshaking for flow control, give amp;xo. Padding information should still be included so that routines can make better decisions about costs, but actual pad characters will not be transmitted.

If the terminal has a "meta key" which acts as a shift key, setting the 8th bit of any character transmitted, then this fact can be indicated with amp;km. Otherwise, software will assume that the 8th bit is parity and it will usually be cleared. If strings exist to turn this "meta mode" on and off, they can be given as amp;mm and amp;mo.

If the terminal has more lines of memory than will fit on the screen at once, the number of lines of memory can be indicated with amp;lm. An explicit value of 0 indicates that the number of lines is not fixed, but that there is still more memory than fits on the screen.

If the terminal is one of those supported by the Unix system virtual terminal protocol, the terminal number can be given as amp;vt.

Media copy strings which control an auxiliary printer connected to the terminal can be given as amp;ps: print the contents of the screen; amp;pf: turn off the printer; and amp;po: turn on the printer. When the printer is on, all text sent to the terminal will be sent to the printer. It is undefined whether the text is also displayed on the terminal screen when the printer is on. A variation amp;pO takes one parameter and leaves the printer on for as many characters as the value of the parameter, then turns the printer off. The parameter should not exceed 255. All text, including amp;pf, is transparently passed to the printer while amp;pO is in effect.

Strings to program function keys can be given as amp;pk, amp;pl, and amp;px. Each of these strings takes two parameters: the function key number to program (from 0 to 9) and the string to program it with. Function key numbers out of this range may program undefined keys in a terminal-dependent manner. The differences among the capabilities are that amp;pk causes pressing the given key to be the same as the user typing the given string; amp;pl causes the string to be executed by the terminal in local mode; and amp;px causes the string to be transmitted to the computer. Unfortunately, due to lack of a definition for string parameters in termcap, only terminfo(5) supports these capabilities.

For the xterm(1) terminal emulator the traditional behavior in FreeBSD when exiting a pager such as less(1) or more(1), or an editor such as vi(1) is NOT to clear the screen after the program exits. If you prefer to clear the screen there are a number of "xterm-clear" entries that add this capability in the termcap file that you can use directly, or as examples.

Glitches and Braindamage

Hazeltine terminals, which do not allow `~' characters to be displayed, should indicate amp;hz.

The amp;nc capability, now obsolete, formerly indicated Datamedia terminals, which echo amp;\r \n for carriage return then ignore a following linefeed.

Terminals that ignore a linefeed immediately after an amp;am wrap, such as the Concept, should indicate amp;xn.

If amp;ce is required to get rid of standout (instead of merely writing normal text on top of it), amp;xs should be given.

Teleray terminals, where tabs turn all characters moved over to blanks, should indicate amp;xt (destructive tabs). This glitch is also taken to mean that it is not possible to position the cursor on top of a "magic cookie", and that to erase standout mode it is necessary to use delete and insert line.

The Beehive Superbee, which is unable to correctly transmit the ESC or amp;^C characters, has amp;xb, indicating that the "amp;famp;1" key is used for ESC and "amp;famp;2" for ^C. (Only certain Superbees have this problem, depending on the ROM.)

Other specific terminal problems may be corrected by adding more capabilities of the form x x.

Similar Terminals

If there are two very similar terminals, one can be defined as being just like the other with certain exceptions. The string capability amp;tc can be given with the name of the similar terminal. This capability must be last, and the combined length of the entries must not exceed 1024. The capabilities given before amp;tc override those in the terminal type invoked by amp;tc. A capability can be canceled by placing amp;xx@ to the left of the amp;tc invocation, where amp;xx is the capability. For example, the entry
hn|2621-nl:ks@:ke@:tc=2621:

defines a "2621-nl" that does not have the amp;ks or amp;ke capabilities, hence does not turn on the function key labels when in visual mode. This is useful for different modes for a terminal, or for different user preferences.

FILES

/usr/share/misc/termcap File containing terminal descriptions.
/usr/share/misc/termcap.db
  Hash database file containing terminal descriptions (see cap_mkdb(1)).

SEE ALSO

cap_mkdb(1), ex(1), more(1), tset(1), ul(1), vi(1), xterm(1), ncurses(3), printf(3), termcap(3), term(5)

CAVEATS AND BUGS

The Note: termcap functions were replaced by terminfo(5) in AT&T V Release 2.0. The transition will be relatively painless if capabilities flagged as "obsolete" are avoided.

Lines and columns are now stored by the kernel as well as in the termcap entry. Most programs now use the kernel information primarily; the information in this file is used only if the kernel does not have any information.

The amp;vi(1) program allows only 256 characters for string capabilities, and the routines in termlib(3) do not check for overflow of this buffer. The total length of a single entry (excluding only escaped newlines) may not exceed 1024.

Not all programs support all entries.

HISTORY

The termcap file format appeared in BSD 3 .

TERMCAP (5) December 13, 2009

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Ken Thompson has an automobile which he helped design. Unlike most automobiles, it has neither speedometer, nor gas gauge, nor any of the other numerous idiot lights which plague the modern driver. Rather, if the driver makes a mistake, a giant “?” lights up in the center of the dashboard. “The experienced driver,” says Thompson, “will usually know what's wrong.”