terminfo - terminal capability database




The terminfo(5) database describes terminals used by screen-oriented programs such as nvi(1), rogue(1) and libraries such as curses. The terminfo database describes terminals by giving a set of capabilities that they have, by specifying how to perform screen operations, and by specifying padding requirements and initialization sequences.

Users who want terminfo database entries that are not precompiled with INTERIX should use the file /usr/share/terminfo.src as an example of terminfo entries, and should use the tic(1) command to compile new entries.

Entries in terminfo(5) consist of a sequence of ',' separated fields (embedded commas may be escaped with a backslash or notated as \072). White space after the ',' separator is ignored. The first entry for each terminal gives the names which 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 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, 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 a mode suffix. Thus, a vt100 in 132 column mode would be vt100-w. The following suffixes should be used where possible:

Suffix Meaning Example
-am With automargins (usually the default) vt100-am
-m Mono mode; suppress color ansi-m
-mc Magic cookie; spaces when highlighting wy30-mc
-na No arrow keys (leave them in local) c100-na
-nam Without automatic margins vt100-nam
-nl No status line att4415-nl
-nn Number of lines on the screen aaa-60
-np Number of pages of memory c100-4p
-ns No status line hp2626-ns
-rv Reverse video c100-rv
-s Enable status line vt100-s
-vb Use visible bell instead of beep wy370-vb
-w Wide mode (> 80 columns, usually 132) vt100-w


The following is a complete table of the capabilities included in a terminfo description block and available to terminfo-using code. In each line of the table,

The variable is the name by which the programmer (at the terminfo level) accesses the capability.

The capname is the short name used in the text of the database, and is used by a person updating the database. Whenever possible, capnames are chosen to be the same as or similar to the ANSI X3.64-1979 standard. Semantics are also intended to match those of the specification.

The termcap code is the old termcap capability name (some capabilities are new, and have names which termcap did not originate).

Capability names have no hard length limit, but an informal limit of 5 characters has been adopted to keep them short and to allow the tabs in the source file Caps to line up nicely.

Finally, the description field attempts to convey the semantics of the capability. You may find some codes in the description field:

indicates that padding may be specified
in the description field indicates that the string is passed through tparm with parms as given (#i).
indicates that padding may vary in proportion to the number of lines affected
indicates the ith parameter.

These are the boolean capabilities:

Variable Name Termcap Description
auto_left_margin bw bw cub1 wraps from column 0 to last column
auto_right_margin am am terminal has automatic margins
no_esc_ctlc xsb xb beehive (f1=escape, f2=ctrl C)
ceol_standout_glitch xhp xs standout not erased by overwriting (hp)
eat_newline_glitch xenl xn newline ignored after 80 cols (concept)
erase_overstrike eo eo can erase overstrikes with a blank
generic_type gn gn generic line type
hard_copy hc hc hardcopy terminal
has_meta_key km km Has a meta key, sets msb high
has_status_line hs hs has extra status line
insert_null_glitch in in insert mode distinguishes nulls
memory_above da da display may be retained above the screen
memory_below db db display may be retained below the screen
move_insert_mode mir mi safe to move while in insert mode
move_standout_mode msgr ms safe to move while in standout mode
over_strike os os terminal can overstrike
status_line_esc_ok eslok es escape can be used on the status line
dest_tabs_magic_smso xt xt tabs destructive, magic so char (t1061)
tilde_glitch hz hz cannot print (hazeltine)
transparent_underline ul ul underline character overstrikes
xon_xoff xon xo terminal uses xon/xoff handshaking
needs_xon_xoff nxon nx padding will not work, xon/xoff required
prtr_silent mc5i 5i printer will not echo on screen
hard_cursor chts HC cursor is hard to see
non_rev_rmcup nrrmc NR smcup does not reverse rmcup
no_pad_char npc NP pad character does not exist
non_dest_scroll_region ndscr ND scrolling region is non-destructive
can_change ccc cc terminal can redefine existing colors
back_color_erase bce ut screen erased with background color
col_addr_glitch xhpa YA only positive motion for hpa/mhpa caps
cr_cancels_micro_mode crxm YB using cr turns off micro mode
has_print_wheel daisy YC printer needs operator to change character set
row_addr_glitch xvpa YD only positive motion for vpa/mvpa caps
semi_auto_right_margin sam YE printing in last column causes cr
cpi_changes_res cpix YF changing character pitch changes resolution
hue_lightness_saturation hls hl terminal uses only HLS color notation (tektronix)
lpi_changes_res lpix YG changing line pitch changes resolution

This capability is described as a boolean in the XSI Curses standard, but is an (undocumented) string capability in SVr4. It is a boolean here.

Variable Name Termcap Description
get_mouse getm Gm Curses should get button events

These are the numeric capabilities:

Variable Name Termcap Description
columns cols co number of columns in a line
init_tabs it it tabs initially every # spaces
lines lines li number of lines on screen or page
lines_of_memory lm lm lines of memory if > line. 0 => varies
magic_cookie_glitch xmc sg number of blank chars left by smso or rmso
padding_baud_rate pb pb lowest baud rate where padding needed
virtual_terminal vt vt virtual terminal number
width_status_line wsl ws columns in status line
num_labels nlab Nl number of labels on screen
label_height lh lh rows in each label
label_width lw lw columns in each label
max_attributes ma ma maximum combined attributes terminal can handle
maximum_windows wnum MW maximum number of definable windows
max_colors colors Co maximum numbers of colors on screen
max_pairs pairs pa maximum number of color-pairs on screen
no_color_video ncv 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.

Variable Name Termcap Description
buffer_capacity bufsz Ya numbers of bytes buffered before printing
dot_vert_spacing spinv Yb spacing of pins vertically in pins per inch
dot_horz_spacing spinh Yc spacing of dots horizontally in dots per inch
max_micro_address maddr Yd maximum value in micro_..._address
max_micro_jump mjump Ye maximum value in parm_..._micro
micro_char_size mcs Yf character size when in micro mode
micro_line_size mls Yg line size when in micro mode
number_of_pins npins Yh numbers of pins in print-head
output_res_char orc Yi horizontal resolution in units per line
output_res_line orl Yj vertical resolution in units per line
output_res_horz_inch orhi Yk horizontal resolution in units per inch
output_res_vert_inch orvi Yl vertical resolution in units per inch
print_rate cps Ym print rate in chars per second
wide_char_size widcs Yn character step size when in double wide mode
buttons btns BT number of buttons on mouse
bit_image_entwining bitwin Yo number of passed for each bit-image row
bit_image_type bitype Yp type of bit-image device

These are the string capabilities:

Variable Name Termcap Description
back_tab cbt bt back tab (P)
bell bel bl audible signal (bell) (P)
carriage_return cr cr carriage return (P*)
change_scroll_region csr cs change region to line #1 to line #2 (P)
clear_all_tabs tbc ct clear all tab stops (P)
clear_screen clear cl clear screen and home cursor (P*)
column_address hpa ch horizontal position #1, absolute (P)
command_character cmdch CC terminal settable cmd character in prototype !?
cursor_address cup cm move to row #1 columns #2
cursor_down cud1 do down one line
cursor_home home ho home cursor (if no cup)
cursor_invisible civis vi make cursor invisible
cursor_left cub1 le move left one space
cursor_mem_address mrcup CM memory relative cursor addressing
cursor_normal cnorm ve make cursor appear normal (undo civis/cvvis)
cursor_right cuf1 nd move right one space
cursor_to_ll ll ll last line, first column (if no cup)
cursor_up cuu1 up up one line
cursor_visible cvvis vs make cursor very visible
delete_character dch1 dc delete character (P*)
delete_line dl1 dl delete line (P*)
dis_status_line dsl ds disable status line
down_half_line hd hd half a line down
enter_alt_charset_mode smacs as start alternate character set (P)
enter_blink_mode blink mb turn on blinking
enter_bold_mode bold md turn on bold (extra bright) mode
enter_ca_mode smcup ti string to start programs using cup
enter_delete_mode smdc dm enter delete mode
enter_dim_mode dim mh turn on half-bright mode
enter_insert_mode smir im enter insert mode
enter_secure_mode invis mk turn on blank mode (characters invisible)
enter_protected_mode prot mp turn on protected mode
enter_reverse_mode rev mr turn on reverse video mode
enter_standout_mode smso so begin standout mode
enter_underline_mode smul us begin underline mode
erase_chars ech ec erase #1 characters (P)
exit_alt_charset_mode rmacs ae end alternate character set (P)
exit_attribute_mode sgr0 me turn off all attributes
exit_ca_mode rmcup te strings to end programs using cup
exit_delete_mode rmdc ed end delete mode
exit_insert_mode rmir ei exit insert mode
exit_standout_mode rmso se exit standout mode
exit_underline_mode rmul ue exit underline mode
flash_screen flash vb visible bell (may not move cursor)
form_feed ff ff hardcopy terminal page eject (P*)
from_status_line fsl fs return from status line
init_1string is1 i1 initialization string
init_2string is2 is initialization string
init_3string is3 i3 initialization string
init_file if if name of initialization file
insert_character ich1 ic insert character (P)
insert_line il1 al insert line (P*)
insert_padding ip ip insert padding after inserted character
key_backspace kbs kb backspace key
key_catab ktbc ka clear-all-tabs key
key_clear kclr kC clear-screen or erase key
key_ctab kctab kt clear-tab key
key_dc kdch1 kD delete-character key
key_dl kdl1 kL delete-line key
key_down kcud1 kd down-arrow key
key_eic krmir kM sent by rmir or smir in insert mode
key_eol kel kE clear-to-end-of-line key
key_eos ked kS clear-to-end-of-screen key
key_f[0-9] kf[0-9] k[0-9] function keys F0 through f9
key_f10 kf10 k; F10 function key
key_home khome kh home key
key_ic kich1 kI insert-character key
key_il kil1 kA insert-line key
key_left kcub1 kl left-arrow key
key_ll kll kH last-line key
key_npage knp kN next-page key
key_ppage kpp kP prev-page key
key_right kcuf1 kr right-arrow key
key_sf kind kF scroll-forward key
key_sr kri kR scroll-backward key
key_stab khts kT set-tab key
key_up kcuu1 ku up-arrow key
keypad_local rmkx ke leave 'keyboard_transmit' mode
keypad_xmit smkx ks enter 'keyboard_transmit' mode
lab_fn lfn ln label on function key fn if not fn; n is a value from 0-10
meta_off rmm mo turn off meta mode
meta_on smm mm turn on meta mode (8th-bit on)
newline nel nw newline (behave like cr followed by lf)
pad_char pad pc padding char (instead of null)
parm_dch dch DC delete #1 chars (P*)
parm_delete_line dl DL delete #1 lines (P*)
parm_down_cursor cud DO down #1 lines (P*)
parm_ich ich IC insert #1 chars (P*)
parm_index indn SF scroll forward #1 lines (P)
parm_insert_line il AL insert #1 lines (P*)
parm_left_cursor cub LE move #1 chars to the left (P)
parm_right_cursor cuf RI move #1 chars to the right (P*)
parm_rindex rin SR scroll back #1 lines (P)
parm_up_cursor cuu UP up #1 lines (P*)
pkey_key pfkey pk program function key #1 to type string #2
pkey_local pfloc pl program function key #1 to execute string #2
pkey_xmit pfx px program function key #1 to transmit string #2
print_screen mc0 ps print contents of screen
prtr_off mc4 pf turn off printer
prtr_on mc5 po turn on printer
repeat_char rep rp repeat char #1 #2 times (P*)
reset_1string rs1 r1 reset string
reset_2string rs2 r2 reset string
reset_3string rs3 r3 reset string
reset_file rf rf name of reset file
restore_cursor rc rc restore cursor to last position of sc
row_address vpa cv vertical position #1 absolute (P)
save_cursor sc sc save current cursor position (P)
scroll_forward ind sf scroll text up (P)
scroll_reverse ri sr scroll text down (P)
set_attributes sgr sa define video attributes #1-#9 (PG9)
set_tab hts st set a tab in every row, current columns
set_window wind wi current window is lines #1-#2 cols #3-#4
tab ht ta tab to next 8-space hardware tab stop
to_status_line tsl ts move to status line
underline_char uc uc underline char and move past it
up_half_line hu hu half a line up
init_prog iprog iP path name of program for initialization
key_a1 ka1 K1 upper left of keypad
key_a3 ka3 K3 upper right of keypad
key_b2 kb2 K2 center of keypad
key_c1 kc1 K4 lower left of keypad
key_c3 kc3 K5 lower right of keypad
prtr_non mc5p pO turn on printer for #1 bytes
char_padding rmp rP like ip but when in insert mode
acs_chars acsc ac graphics charset pairs -- def=vt100
plab_norm pln pn program label #1 to show string #2
key_btab kcbt kB back-tab key
enter_xon_mode smxon SX turn on xon/xoff handshaking
exit_xon_mode rmxon RX turn off xon/xoff handshaking
enter_am_mode smam SA turn on automatic margins
exit_am_mode rmam RA turn off automatic margins
xon_character xonc XN XON character
xoff_character xoffc XF XOFF character
ena_acs enacs eA enable alternate char set
label_on smln LO turn on soft labels
label_off rmln LF turn off soft labels
key_beg kbeg 1 begin key
key_cancel kcan @2 cancel key
key_close kclo @3 close key
key_command kcmd @4 command key
key_copy kcpy @5 copy key
key_create kcrt @6 create key
key_end kend @7 end key
key_enter kent @8 enter/send key
key_exit kext @9 exit key
key_find kfnd @0 find key
key_help khlp %1 help key
key_mark kmrk %2 mark key
key_message kmsg %3 message key
key_move kmov %4 move key
key_next knxt %5 next key
key_open kopn %6 open key
key_options kopt %7 options key
key_previous kprv %8 previous key
key_print kprt %9 print key
key_redo krdo %0 redo key
key_reference kref &1 reference key
key_refresh krfr &2 refresh key
key_replace krpl &3 replace key
key_restart krst &4 restart key
key_resume kres &5 resume key
key_save ksav &6 save key
key_suspend kspd &7 suspend key
key_undo kund &8 undo key
key_sbeg kBEG &9 shifted key
key_scancel kCAN &0 shifted key
key_scommand kCMD *1 shifted key
key_scopy kCPY *2 shifted key
key_screate kCRT *3 shifted key
key_sdc kDC *4 shifted key
key_sdl kDL *5 shifted key
key_select kslt *6 select key
key_send kEND *7 shifted key
key_seol kEOL *8 shifted key
key_sexit kEXT *9 shifted key
key_sfind kFND *0 shifted key
key_shelp kHLP #1 shifted key
key_shome kHOM #2 shifted key
key_sic kIC #3 shifted key
key_sleft kLFT #4 shifted key
key_smessage kMSG %a shifted key
key_smove kMOV %b shifted key
key_snext kNXT %c shifted key
key_soptions kOPT %d shifted key
key_sprevious kPRV %e shifted key
key_sprint kPRT %f shifted key
key_sredo kRDO %g shifted key
key_sreplace kRPL %h shifted key
key_sright kRIT %i shifted key
key_srsume kRES %j shifted key
key_ssave kSAV !1 shifted key
key_ssuspend kSPD !2 shifted key
key_sundo kUND !3 shifted key
req_for_input rfi RF send next input char (for ptys)
key_f[13-24] kf[13-24] (shift-F1 - shift-F12)
key_f[25-36] kf[25-36]
key_f[46-63] kf[46-63]
clr_bol el1 cb Clear to beginning of line
clear_margins mgc MC clear right and left soft margins
set_left_margin smgl ML set left soft margin
set_right_margin smgr MR set right soft margin
label_format fln Lf label format
set_clock sclk SC set clock, #1 hrs #2 mins #3 secs
display_clock dclk DK display clock at (#1,#2)
remove_clock rmclk RC remove clock
create_window cwin CW define a window #1 from #2, #3 to #4, #5
goto_window wingo WG go to window #1
hangup hup HU hang-up phone
dial_phone dial DI dial number #1
quick_dial qdial QD dial number #1 without checking
tone tone TO select touch tone dialing
pulse pulse PU select pulse dialling
flash_hook hook fh flash switch hook
fixed_pause pause PA pause for 2-3 seconds
wait_tone wait WA wait for dial-tone
user[0-9] u[0-9] u[0-9] User strings #0-#9
orig_pair op op Set default pair to its original value
orig_colors oc oc Set all color pairs to the original ones
initialize_color initc Ic initialize color #1 to (#2,#3,#4)
initialize_pair initp Ip Initialize color pair #1 to fg=(#2,#3,#4), bg=(#5,#6,#7)
set_color_pair scp sp Set current color pair to #1
set_foreground setf Sf Set foreground color #1
set_background setb Sb Set background color #1
change_char_pitch cpi ZA Change number of characters per inch
change_line_pitch lpi ZB Change number of lines per inch
change_res_horz chr ZC Change horizontal resolution
change_res_vert cvr ZD Change vertical resolution
define_char defc ZE Define a character
enter_doublewide_mode swidm ZF Enter double-wide mode
enter_draft_quality sdrfq ZG Enter draft-quality mode
enter_italics_mode sitm ZH Enter italic mode
enter_leftward_mode slm ZI Start leftward carriage motion
enter_micro_mode smicm ZJ Start micro-motion mode
enter_near_letter_quality snlq ZK Enter NLQ mode
enter_normal_quality snrmq ZL Enter normal-quality mode
enter_shadow_mode sshm ZM Enter shadow-print mode
enter_subscript_mode ssubm ZN Enter subscript mode
enter_superscript_mode ssupm ZO Enter superscript mode
enter_upward_mode sum ZP Start upward carriage motion
exit_doublewide_mode rwidm ZQ End double-wide mode
exit_italics_mode ritm ZR End italic mode
exit_leftward_mode rlm ZS End left-motion mode
exit_micro_mode rmicm ZT End micro-motion mode
exit_shadow_mode rshm ZU End shadow-print mode
exit_subscript_mode rsubm ZV End subscript mode
exit_superscript_mode rsupm ZW End superscript mode
exit_upward_mode rum ZX End reverse character motion
micro_column_address mhpa ZY Like column_address in micro mode
micro_down mcud1 ZZ Like cursor_down in micro mode
micro_left mcub1 Za Like cursor_left in micro mode
micro_right mcuf1 Zb Like cursor_right in micro mode
micro_row_address mvpa Zc Like row_address in micro mode
micro_up mcuu1 Zd Like cursor_up in micro mode
order_of_pins porder Ze Match software bits to print-head pins
parm_down_micro mcud Zf Like parm_down_cursor in micro mode
parm_left_micro mcub Zg Like parm_left_cursor in micro mode
parm_right_micro mcuf Zh Like parm_right_cursor in micro mode
parm_up_micro mcuu Zi Like parm_up_cursor in micro mode
select_char_set scs Zj Select character set
set_bottom_margin smgb Zk Set bottom margin at current line
set_bottom_margin_parm smgbp Zl Set bottom margin at line #1 or #2 lines from bottom
set_left_margin_parm smglp Zm Set left (right) margin at column #1 (#2)
set_right_margin_parm smgrp Zn Set right margin at column #1
set_top_margin smgt Zo Set top margin at current line
set_top_margin_parm smgtp Zp Set top (bottom) margin at row #1 (#2)
start_bit_image sbim Zq Start printing bit image bgraphics
start_char_set_def scsd Zr Start character set definition
stop_bit_image rbim Zs Stop printing bit image graphics
stop_char_set_def rcsd Zt End definition of character aset
subscript_characters subcs Zu List of subscriptable characters
superscript_characters supcs Zv List of superscriptable characters
these_cause_cr docr Zw Printing any of these chars causes CR
zero_motion zerom Zx No motion for subsequent character
char_set_names csnm Zy List of character set names
key_mouse kmous Km Mouse event has occurred
mouse_info minfo Mi Mouse status information
req_mouse_pos reqmp RQ Request mouse position
get_mouse getm Gm Curses should get button events
set_a_foreground setaf AF Set ANSI foreground color
set_a_background setab AB Set ANSI background color
pkey_plab pfxl xl Program function key #1 to type string #2 and show string #3
device_type devt dv Indicate language/codeset support
code_set_init csin ci Init sequence for multiple codesets
set0_des_seq s0ds s0 Shift to code set 0 (EUC set 0, ASCII)
set1_des_seq s1ds s1 Shift to code set 1
set2_des_seq s2ds s2 Shift to code set 2
set3_des_seq s3ds s3 Shift to code set 3
set_lr_margin smglr ML Set both left and right margins to #1, #2
set_tb_margin smgtb MT Sets both top and bottom margins to #1, #2
bit_image_repeat birep Xy Repeat bit image cell #1 #2 times
bit_image_newline binel Zz Move to next row of the bit image
color_names colornm Yw Give name for color #1
set_color_band setcolor Yz Change to ribbon color #1
set_page_length slines YZ Set page length to #1 lines
display_pc_char dispc S1 Display PC character
enter_pc_charset_mode smpch S2 Enter PC character display mode
exit_pc_charset_mode rmpch S3 Exit PC character display mode
enter_scancode_mode smsc S4 Enter PC scancode mode
exit_scancode_mode rmsc S5 Exit PC scancode mode
pc_term_options pctrm S6 PC terminal options
scancode_escape scesc S7 Escape for scancode emulation
alt_scancode_esc scesa S8 Alternate escape for scancode emulation
bit_image_carriage_return bicr Yv Move to beginning of same row
define_bit_image_region defbi Yx Define rectangular bit image region
end_bit_image_region endbi Yy End a bit-image region

The XSI Curses standard added these. They are probably in some post-4.1 version of System V curses as well, but because XSI Curses lists them is strict alphabetical order we do not know whether this is the right binary order. The ncurses termcap names for them are invented; according to the XSI Curses standard, they have no termcap names. If your compiled terminfo entries use these, they may not be binary-compatible with System V terminfo entries after SVr4.1; beware!

Variable Name Termcap Description
enter_horizontal_hl_mode ehhlm Xh Enter horizontal highlight mode
enter_left_hl_mode elhlm Xl Enter left highlight mode
enter_low_hl_mode elohlm Xo Enter low highlight mode
enter_right_hl_mode erhlm Xr Enter right highlight mode
enter_top_hl_mode ethlm Xt Enter top highlight mode
enter_vertical_hl_mode evhlm Xv Enter vertical highlight mode

A sample entry

The following entry, describing an ANSI-standard terminal, is representative of what a terminfo entry for a modern terminal typically looks like.

ansi|ansi/pc-term compatible with color, mc5i, colors#8, ncv#3, pairs#64, cub=\E[%p1%dD, cud=\E[%p1%dB, cuf=\E[%p1%dC, cuu=\E[%p1%dA, dch=\E[%p1%dP, dl=\E[%p1%dM, ech=\E[%p1%dX, el1=\E[1K, hpa=\E[%p1%dG, ht=\E[I, ich=\E[%p1%d@, il=\E[%p1%dL, indn=\E[%p1%dS, kbs=^H, kcbt=\E[Z, kcub1=\E[D, kcud1=\E[B, kcuf1=\E[C, kcuu1=\E[A, kf1=\E[M, kf10=\E[V, kf11=\E[W, kf12=\E[X, kf2=\E[N, kf3=\E[O, kf4=\E[P, kf5=\E[Q, kf6=\E[R, kf7=\E[S, kf8=\E[T, kf9=\E[U, kich1=\E[L, mc4=\E[4i, mc5=\E[5i, nel=\r\E[S, op=\E[37;40m, rep=%p1%c\E[%p2%{1}%-%db, rin=\E[%p1%dT, s0ds=\E(B, s1ds=\E)B, s2ds=\E*B, s3ds=\E+B, setab=\E[4%p1%dm, setaf=\E[3%p1%dm, setb=\E[4%?%p1%{1}%=%t4%e%p1%{3}%=%t6%e%p1%{4}%=%t1%e%p1%{6}%=%t3%e%p1%d%;m, setf=\E[3%?%p1%{1}%=%t4%e%p1%{3}%=%t6%e%p1%{4}%=%t1%e%p1%{6}%=%t3%e%p1%d%;m, sgr=\E[0;10%?%p1%t;7%;%?%p2%t;4%;%?%p3%t;7%;%?%p4%t;5%;%?%p6%t;1%;%?%p7%t;8%;%?%p8%t;11%;%?%p9%t;12%;m, sgr0=\E[0;10m, tbc=\E[2g, u6=\E[%d;%dR, u7=\E[6n, u8=\E[?%[;0123456789]c, u9=\E[c, vpa=\E[%p1%dd,

Entries may continue onto multiple lines by placing white space at the beginning of each line except the first. Comments may be included on lines beginning with "#". Capabilities in terminfo are of three types: Boolean capabilities which indicate that the terminal has some particular feature, numeric capabilities giving the size of the terminal or the size of particular delays, and string capabilities, which give a sequence which can be used to perform particular terminal operations.

Types of capabilities

All capabilities have names. For instance, the fact that ANSI-standard terminals have automatic margins (i.e., an automatic return and line-feed when the end of a line is reached) is indicated by the capability am. Hence the description of ansi includes am. Numeric capabilities are followed by the character '#' and then the value. Thus cols, which indicates the number of columns the terminal has, gives the value '80' for ansi.

Finally, string valued capabilities, such as el (clear to end of line sequence) are given by the two-character code, an '=', and then a string ending at the next following ','.

A number of escape sequences are provided in the string valued capabilities for easy encoding of characters there. Both \E and \e map to an ESCAPE character, ^x maps to a control-x for any appropriate x, and the sequences \n, \l, \r, \t, \b, \f, and \s give a newline, line-feed, return, tab, backspace, form-feed, and space. Other escapes include \^ for ^, \\ for \, \, for comma, \: for :, and \0 for null. (\0 will produce \200, which does not terminate a string but behaves as a null character on most terminals.) Finally, characters may be given as three octal digits after a \.

A delay in milliseconds may appear anywhere in a string capability, enclosed in $<..> brackets, as in el=\EK$<5>, and padding characters are supplied by tputs(3) to provide this delay. The delay must be a number with at most one decimal place of precision; it may be followed by suffixes '*' or '/' or both. A '*' indicates that the padding required is proportional to the number of lines affected by the operation, and the amount given is the per-affected-unit padding required. (In the case of insert character, the factor is still the number of lines affected.) Normally, padding is advisory if the ddevicehas the xon capability; it is used for cost computation but does not trigger delays. A '/' suffix indicates that the padding is mandatory and forces a delay of the given number of milliseconds even on devices for which xon is present to indicate flow control.

Sometimes individual capabilities must be commented out. To do this, put a period before the capability name. For example, see the second ind in the example above.

Fetching compiled descriptions

To easily test a new terminal description you can set the environment variable TERMINFO to a ppath name of a directory containing the compiled description you are working on and programs will look there rather than in terminfo.

If TERMINFO is not set, the ncurses version of the terminfo reader code will instead look in the directory $HOME/.terminfo for a compiled description. (This extension is not supported under stock System V terminfo/curses.)

If these local lookups fail, the last place tried will be the system terminfo directory, terminfo.

Preparing descriptions

We now outline how to prepare descriptions of terminals. The most effective way to prepare a terminal description is by imitating the description of a similar terminal in terminfo and to build up a description gradually, using partial descriptions with vi(1) or some other screen-oriented program to check that they are correct. Be aware that a very unusual terminal may expose deficiencies in the ability of the terminfo file to describe it or bugs in the screen-handling code of the test program.

To get the padding for insert line right (if the terminal manufacturer did not document it) a severe test is to edit /etc/passwd at 9600 baud, delete 16 or so lines from the middle of the screen, then hit the 'u' key several times quickly. If the terminal 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 for the terminal is given by the cols numeric capability. If the terminal is a CRT, then the number of lines on the screen is given by the lines capability. If the terminal wraps around to the beginning of the next line when it reaches the right margin, then it should have the am capability. If the terminal can clear its screen, leaving the cursor in the home position, then this is given by the clear string capability. If the terminal overstrikes (rather than clearing a position when a character is struck over) then it should have the os capability. If the terminal is a printing terminal, with no soft copy unit, give it both hc and os. (os applies to storage scope terminals, such as TEKTRONIX 4010 series, as well as 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 cr. (Normally this will be carriage return, control M.) If there is a code to produce an audible signal (bell, beep, etc) give this as bel.

If there is a code to move the cursor one position to the left (such as backspace) that capability should be given as cub1. Similarly, codes to move to the right, up, and down should be given as cuf1, cuu1, and cud1. These local cursor motions should not alter the text they pass over, for example, you would not normally use 'cuf1=\ ' because the space would erase the character moved over.

A very important point here is that the local cursor motions encoded in terminfo are undefined at the left and top edges of a CRT terminal. Programs should never attempt to backspace around the left edge, unless bw is given, and never attempt to go up locally off the top. In order to scroll text up, a program will go to the bottom left corner of the screen and send the ind (index) string.

To scroll text down, a program goes to the top left corner of the screen and sends the ri (reverse index) string. The strings ind and ri are undefined when not on their respective corners of the screen.

Parameterized versions of the scrolling sequences are indn and rin which have the same semantics as ind and ri except that they take one parameter, and scroll that many lines. They are also undefined except at the appropriate edge of the screen.

The am capability tells whether the cursor sticks at the right edge of the screen when text is output, but this does not necessarily apply to a cuf1 from the last column. The only local motion which is defined from the left edge is if bw is given, then a cub1 from the left edge will move to the right edge of the previous row. If bw is not given, the effect is undefined. This is useful for drawing a box around the edge of the screen, for example. If the terminal has switch selectable automatic margins, the terminfo file usually assumes that this is on; i.e., am. If the terminal has a command which moves to the first column of the next line, that command can be given as nel (newline). It does not matter if the command clears the remainder of the current line, so if the terminal has no cr and lf it may still be possible to craft a working nel out of one or both of them.

These capabilities suffice to describe hard-copy and glass-tty terminals. Thus the model 33 teletype is described as

  33|tty33|tty|model 33 teletype,
  bel=^G, cols#72, cr=^M, cud1=^J, hc, ind=^J, os,

while the Lear Siegler ADM-3 is described as

  adm3|3|lsi adm3,
  am, bel=^G, clear=^Z, cols#80, cr=^M, cub1=^H, cud1=^J,
  ind=^J, lines#24,

Parameterized strings

Cursor addressing and other strings requiring parameters in the terminal are described by a parameterized string capability, with printf(3)-like escapes %x in it. For example, to address the cursor, the cup capability is given, using two parameters: the row and column to address 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 mrcup.

The parameter mechanism uses a stack and special % codes to manipulate it. Typically a sequence will push one of the parameters onto the stack and then print it in some format. Often more complex operations are necessary.

The % encodings have the following meanings:

%% outputs '%'
%d print pop() as in printf
%2d print pop() like %2d
%3d print pop() like %3d
%03d as in printf
%x print pop() as in printf
%2x print pop() like %2x
%3x print pop() like %3x
%03x as in printf
%c print pop() gives %c
%s print pop() gives %s
%p[1-9] push ith parm
%P[a-z] set variable [a-z] to pop()
%g[a-z] get variable [a-z] and push it
%'c' char constant c
%{nn} integer constant nn
%+ %- %* %/ %m arithmetic (%m is mod): push(pop() op pop())
%& %| %^ bit operations: push(pop() op pop())
%= %> %< logical operations: push(pop() op pop())
%A, %O logical and & or operations (for conditionals)
%! %~ unary operations push(op pop())
%i add 1 to first two parms (for ANSI terminals)
%? expr %t thenpart %e elsepart %;
if-then-else, %e elsepart is optional.
else-if's are possible ala Algol 68:
%? c1 %t b1 %e c2 %t b2 %e c3 %t b3 %e c4 %t b4 %e %;

ci are conditions, bi are bodies.

Binary operations are in postfix form with the operands in the usual order. That is, to get x-5 one would use "%gx%{5}%-".

Consider the HP2645, 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 rows and columns is inverted here, and that the row and column are printed as two digits. Thus its cup capability is cup=6\E&%p2%2dc%p1%2dY.

The Microterm needs the current row and column sent preceded by a ^T, with the row and column simply encoded in binary, cup=^T%p1%c%p2%c. Terminals which use %c need to be able to backspace the cursor (cub1), and to move the cursor up one line on the screen (cuu1). This is necessary because it is not always safe to transmit \n ^D and \r, as the system may change or discard them. (The library routines dealing with terminfo set tty modes so that tabs are never expanded, so \t is safe to send. This turns out to be essential for the Ann Arbor 4080.)

A final example is the which uses row and column offset by a blank character, thus cup=\E=%p1%' '%+%c%p2%' '%+%c. After sending '\E=', this pushes the first parameter, pushes the ASCII value for a space (32), adds them (pushing the sum on the stack in place of the two previous values) and outputs that value as a character. Then the same is done for the second parameter. More complex arithmetic is possible using the stack.

If the terminal has row or column absolute cursor addressing, these can be given as single parameter capabilities hpa (horizontal position absolute) and vpa (vertical position absolute). Sometimes these are shorter than the more general two parameter sequence (as with the hp2645) and can be used in preference to cup. If there are parameterized local motions (e.g., move n spaces to the right) these can be given as cud, cub, cuf, and cuu with a single parameter indicating how many spaces to move. These are primarily useful if the terminal does not have cup, such as the 4025.

Cursor Motions

If the terminal has a fast way to home the cursor (to very upper left corner of screen) then this can be given as home; similarly a fast way of getting to the lower left-hand corner can be given as ll; this may involve going up with cuu1 from the home position, but a program should never do this itself (unless 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 addressing to (0,0): to the top left corner of the screen, not of memory. (Thus, the \EH sequence on HP terminals cannot be used for home.)

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 el. If the terminal can clear from the current position to the end of the display, then this should be given as ed. Ed is only defined from the first column of a line. (Thus, it can be simulated by a request to delete a large number of lines, if a true ed is not available.)

Insert/delete line and vertical motions

If the terminal can open a new blank line before the line where the cursor is, this should be given as il1; this is done only from the first position of a line. The cursor must then appear on the newly blank line. If the terminal can delete the line which the cursor is on, then this should be given as dl1; this is done only from the first position on the line to be deleted. Versions of il1 and dl1 which take a single parameter and insert or delete that many lines can be given as il and dl. If the terminal has a settable scrolling region (like the vt100) the command to set this can be described with the csr 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 csr on a properly chosen region; the sc and rc (save and restore cursor) commands may be useful for ensuring that your synthesized insert/delete string does not move the cursor. (Note that the ncurses(3x) library does this synthesis automatically, so you need not compose insert/delete strings for an entry with csr).

Yet another way to construct insert and delete might be to use a combination of index with the memory-lock feature found on some terminals (like the HP-700/90 series, which however also has insert/delete).

Inserting lines at the top or bottom of the screen can also be done using ri or ind on many terminals without a true insert/delete line, and is often faster even on terminals with those features.

The boolean non_dest_scroll_region should be set if each scrolling window is effectively a viewport on a screen-sized canvas. To test for this capability, create a scrolling region in the middle of the screen, write something to the bottom line, move the cursor to the top of the region, and do ri followed by dl1 or ind. If the data scrolled off the bottom of the region by the ri rreappears then scrolling is non-destructive. System V and XSI Curses expect that ind, ri, indn, and rin will simulate destructive scrolling; their documentation cautions you not to define csr unless this is true. This curses implementation is more liberal and will do explicit erases after scrolling if ndstr is defined.

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 wind. The four parameters are the starting and ending lines in memory and the starting and ending columns in memory, in that order.

If the terminal can retain display memory above, then the da capability should be given; if display memory can be retained below, then 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 ri may bring down non-blank lines.

Insert/delete character

There are two basic kinds of intelligent terminals with respect to insert/delete character which can be described using terminfo. 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 and 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, you have the second type of terminal. You should therefore give the capability in, which stands for insert null. While these are two logically separate attributes (one line as compared to 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 terminfo database can describe terminals that have an insert mode, and terminals that send a simple sequence to open a blank position on the current line. Give as smir the sequence to get into insert mode. Give as rmir the sequence to leave insert mode. Now give as ich1 any sequence needed to be sent just before sending the character to be inserted. Most terminals with a true insert mode will not give ich1; terminals which send a sequence to open a screen position should give it here.

If your terminal has both, insert mode is usually preferable to ich1. Technically, you should not give both unless the terminal actually requires both to be used in combination. Accordingly, some non-curses applications get confused if both are present; the symptom is doubled characters in an update using insert. This requirement is now rare; most ich sequences do not require previous smir, and most smir insert modes do not require ich1 before each character. Therefore, the new curses actually assumes this is the case and uses either rmir/smir or ich/ich1 as appropriate (but not both). If you have to write an entry to be used under new curses for a terminal old enough to need both, include the rmir/smir sequences in ich1.

If post insert padding is needed, give this as a number of milliseconds in ip (a string option). Any other sequence which may need to be sent after an insert of a single character may also be given in ip. If your terminal needs both to be placed into an 'insert mode' and a special code to precede each inserted character, then both smir/rmir and ich1 can be given, and both will be used. The ich capability, with one parameter, n, will repeat the effects of ich1 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 mir to speed up inserting in this case. Omitting mir will affect only speed. Some terminals (notably Datamedia's) must not have mir because of the way their insert mode works.

Finally, you can specify dch1 to delete a single character, dch with one parameter, n, to delete n and delete mode by giving smdc and rmdc to enter and exit delete mode (any mode the terminal needs to be placed in for dch1 to work).

A command to erase n characters (equivalent to outputting n blanks without moving the cursor) can be given as ech with one parameter.

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 smso and rmso, respectively. If the code to change into or out of standout mode leaves one or even two blank spaces on the screen, as the TVI 912 and Teleray 1061 do, then xmc should be given to tell how many spaces are left.

Codes to begin underlining and end underlining can be given as smul and rmul respectively. If the terminal has a code to underline the current character and move the cursor one space to the right, such as the Microterm Mime, this can be given as uc.

Other capabilities to enter various highlighting modes include blink (blinking) bold (bold or extra bright) dim (dim or half-bright) invis (blanking or invisible text) prot (protected) rev (reverse video) sgr0 (turn off all attribute modes) smacs (enter alternate character set mode) and rmacs (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 modes, this should be given as sgr (set attributes), taking 9 parameters. Each parameter is either 0 or 1, as the corresponding attribute is on or off. The 9 parameters are, in order: standout, underline, reverse, blink, dim, bold, blank, protect, alternate character set. Not all modes need be supported by sgr, only those for which corresponding separate attribute commands exist.

Terminals with the "magic cookie" glitch (xmc deposit special "cookies" when they receive mode-setting sequences, which affect the display algorithm rather than having extra bits for each character. Some terminals, such as the HP 2621, automatically leave standout mode when they move to a new line or the cursor is addressed. Programs using standout mode should exit standout mode before moving the cursor or sending a newline, unless the msgr capability, asserting that it is safe to move in standout mode, is present.

If the terminal has a way of flashing the screen to indicate an error quietly (a bell replacement) then this can be given as flash; 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 make, for example, a non-blinking underline into an easier to find block or blinking underline) give this sequence as cvvis. If there is a way to make the cursor completely invisible, give that as civis. The capability cnorm should be given which undoes the effects of both of these modes.

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 smcup and rmcup. 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 one screen-sized window must be fixed into the terminal for cursor addressing to work properly. This is also used for the TEKTRONIX 4025, where smcup sets the command character to be the one used by terminfo.

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

Keypad handling

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 (this applies, for example, to the unshifted HP 2621 keys). If the keypad can be set to transmit or not transmit, give these codes as smkx and rmkx. 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 kcub1, kcuf1, kcuu1, kcud1, and khome respectively. If there are function keys such as f0, f1, ..., f10, the codes they send can be given as kf0, kf1, ..., kf10. If these keys have labels other than the default f0 through f10, the labels can be given as lf0, lf1, ..., lf10. The codes transmitted by certain other special keys can be given: kll (home down), kbs (backspace), ktbc (clear all tabs), kctab (clear the tab stop in this column), kclr (clear screen or erase key), kdch1 (delete character), kdl1 (delete line), krmir (exit insert mode), kel (clear to end of line), ked (clear to end of screen), kich1 (insert character or enter insert mode), kil1 (insert line), knp (next page), kpp (previous page), kind (scroll forward/down), kri (scroll backward/up), khts (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, the other five keys can be given as ka1, ka3, kb2, kc1, and kc3. These keys are useful when the effects of a 3 by 3 directional pad are needed.

Tabs and initialization

If the terminal has hardware tabs, the command to advance to the next tab stop can be given as ht (usually control I). A "back-tab" command which moves leftward to the next tab stop can be given as cbt. By convention, if the teletype modes indicate that tabs are being expanded by the computer rather than being sent to the terminal, programs should not use ht or cbt even if they are present, since the user may not have the tab stops properly set. If the terminal has hardware tabs which are initially set every n spaces when the terminal is powered up, the numeric parameter it is given, showing the number of spaces the tabs are set to. This is normally used by the tset command to determine whether to set the mode for hardware tab expansion, and whether to set the tab stops. If the terminal has tab stops that can be saved in non-volatile memory, the terminfo description can assume that they are properly set.

Other capabilities include is1, is2, and is3, initialization strings for the terminal, iprog, the path name of a program to be run to initialize the terminal, and 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 terminfo 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: is1; is2; setting tabs using tbc and hts; if; running the program iprog; and finally is3. Most initialization is done with is2. Special terminal modes can be set up without duplicating strings by putting the common sequences in is2 and special cases in is1 and is3. A pair of sequences that does a harder reset from a totally unknown state can be analogously given as rs1, rs2, rf, and rs3, analogous to is2 and if. These strings are output by the reset(1) program, which is used when the terminal gets into a wedged state. Commands are normally placed in rs2 and 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 is2, 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 there are commands to set and clear tab stops, they can be given as tbc (clear all tab stops) and hts (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 is2 or if.

Delays and padding

Many older and slower terminals do not support either XON/XOFF or DTR handshaking, including hardcopy terminals and some very archaic CRTs (including, for example, DEC VT100s). These may require padding characters after certain cursor motions and screen changes.

If the terminal uses xon/xoff handshaking for flow control (that is, it automatically emits ^S back to the host when its input buffers are close to full), set xon. This capability suppresses the emission of padding. You can also set it for memory-mapped console devices effectively that do not have a speed limit. Padding information should still be included so that routines can make better decisions about relative costs, but actual pad characters will not be transmitted.

If pb (padding baud rate) is given, padding is suppressed at baud rates below the value of pb. If the entry has no padding baud rate, then whether padding is emitted or not is completely controlled by xon.

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

Status lines

Some terminals have an extra 'status line' which is not normally used by software (and thus not counted in the terminal's lines capability).

The simplest case is a status line which is cursor-addressable but not part of the main scrolling region on the screen; the Heathkit H19 has a status line of this kind, as would a 24-line VT100 with a 23-line scrolling region set up on initialization. This situation is indicated by the hs capability.

Some terminals with status lines need special sequences to access the status line. These may be expressed as a string with single parameter tsl which takes the cursor to a given zero-origin column on the status line. The capability fsl must return to the main-screen cursor positions bbeforethe last tsl. You may need to embed the string values of sc (save cursor) and rc (restore cursor) in tsl and fsl to accomplish this.

The status line is normally assumed to be the same width as the width of the terminal. If this is untrue, you can specify it with the numeric capability wsl.

A command to erase or blank the status line may be specified as dsl.

The boolean capability eslok specifies that escape sequences, tabs, etc. work ordinarily in the status line.

The ncurses implementation does not yet use any of these capabilities. They are documented here in case they ever become important.

Line graphics

Many terminals have alternate character sets useful for forms-drawing. The terminfo ddatabaseand curses build in support for the drawing characters supported by the VT100, with some characters ffromthe AT&T 4410v1 added. This alternate character set may be specified by the acsc capability.

Glyph name ACS name ASCII default VT100 name
upper left corner ACS_ULCORNER + l
lower left corner ACS_LLCORNER + m
upper right corner ACS_URCORNER + k
lower right corner ACS_LRCORNER + j
tee pointing right ACS_LTEE + t
tee pointing left ACS_RTEE + u
tee pointing up ACS_BTEE + v
tee pointing down ACS_TTEE + w
horizontal line ACS_HLINE - q
vertical line ACS_VLINE | x
large plus or crossover ACS_PLUS + n
scan line 1 ACS_S1 ~ o
scan line 9 ACS_S9 _ s
diamond ACS_DIAMOND + `
checker board (stipple) ACS_CKBOARD : a
degree symbol ACS_DEGREE \ f
plus/minus ACS_PLMINUS # g
bullet ACS_BULLET o ~
arrow pointing left ACS_LARROW < ,
arrow pointing right ACS_RARROW > +
arrow pointing down ACS_DARROW v .
arrow pointing up ACS_UARROW ^ -
board of squares ACS_BOARD # h
lantern symbol ACS_LANTERN # I
solid square block ACS_BLOCK # 0

The best way to define a new device's graphics set is to add a column to a copy of this table for your terminal, giving the character which (when emitted between smacs/rmacs switches) will be rendered as the corresponding graphic. Then read off the VT100/your terminal character pairs right to left in sequence; these become the ACSC string.

Color Handling

Most color terminals are either 'Tektronix-like' or 'HP-like'. Tektronix-like terminals have a predefined set of N colors (where N usually 8), and can set character-cell foreground and background characters independently, mixing them into N * N color-pairs. On HP-like terminals, the use must set each color pair up separately (foreground and background are not independently settable). Up to M color-pairs may be set up from 2*M different colors. ANSI-compatible terminals are Tektronix-like.

Some basic color capabilities are independent of the color method. The numeric capabilities colors and pairs specify the maximum numbers of colors and color-pairs that can be displayed simultaneously. The op (original pair) string resets foreground and background colors to their default values for the terminal. The oc string resets all colors or color-pairs to their default values for the terminal. Some terminals (including many PC terminal emulators) erase screen areas with the current background color rather than the power-up default background; these should have the boolean capability bce.

To change the current foreground or background color on a Tektronix-type terminal, use setaf (set ANSI foreground) and setab (set ANSI background). These take one parameter, the color number. On an HP-like terminal, use scp with a color-pair number parameter to set which color pair is current.

On a Tektronix-like terminal, the capability ccc may be present to indicate that colors can be modified. If so, the initc capability will take a color number (0 to colors - 1)and three more parameters which describe the color. These three parameters default to being interpreted as RGB (Red, Green, Blue) values. If the boolean capability hls is present, they are instead as HLS (Hue, Lightness, Saturation) indices. The ranges are terminal-dependent.

On an HP-like terminal, initp may give a capability for changing a color-pair value. It will take seven parameters; a color-pair number (0 to max_pairs - 1), and two triples describing first background and then foreground colors. These parameters must be (Red, Green, Blue) or (Hue, Lightness, Saturation) depending on hls.

On some color terminals, colors collide with highlights. You can register these collisions with the ncv capability. This is a bit-mask of attributes not to be used when colors are enabled. The correspondence with the attributes understood by curses is as follows:

Attribute Bit Decimal
A_DIM 4 16
A_BOLD 5 32
A_INVIS 6 64

For example, on many IBM PC consoles, the underline attribute collides with the foreground color blue and is not available in color mode. These should have an ncv capability of 2.


If the terminal can move up or down half a line, this can be indicated with hu (half-line up) and hd (half-line down). This is primarily useful for superscripts and subscripts on hard-copy terminals. If a hard-copy terminal can eject to the next page (form feed), give this as ff (usually control 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 rep. The first parameter is the character to be repeated and the second is the number of times to repeat it. Thus, tparm(repeat_char, 'x', 10) is the same as 'xxxxxxxxxx'.

If the terminal has a settable command character, such as the TEKTRONIX 4025, this can be indicated with cmdch. A prototype command character is chosen which is used in all capabilities. This character is given in the cmdch capability to identify it. The following convention is supported on some systems: The environment is to be searched for a CC variable, and if found, all occurrences of the prototype character are replaced with the character in the environment variable.

Terminal descriptions that do not represent a specific kind of known terminal, such as switch, dialup, patch, and network, should include the 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 has a "meta key" which acts as a shift key, setting the 8th bit of any character transmitted, this fact can be indicated with 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 smm and rmm.

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 lm. A value of lm#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 virtual terminal protocol, the terminal number can be given as vt.

Media copy strings which control an auxiliary printer connected to the terminal can be given as mc0: print the contents of the screen, mc4: turn off the printer, and mc5: 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 mc5p 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 mc4, is transparently passed to the printer while an mc5p is in effect.

Strings to program function keys can be given as pfkey, pfloc, and pfx. Each of these strings takes two parameters: the function key number to program (from 0 to 10) and the string to program it with. Function key numbers out of this range may program undefined keys in a terminal dependent manner. The difference between the capabilities is that pfkey causes pressing the given key to be the same as the user typing the given string; pfloc causes the string to be executed by the terminal in local; and pfx causes the string to be transmitted to the computer.


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

Terminals which ignore a line-feed immediately after an am wrap, such as the Concept and vt100, should indicate xenl.

If el is required to get rid of standout (instead of merely writing normal text on top of it), xhp should be given.

Teleray terminals, where tabs turn all characters moved over to blanks, should indicate xt (destructive tabs). Note: the variable indicating this is now 'dest_tabs_magic_smso'; in older versions, it was teleray_glitch. This glitch is also taken to mean that it is not possible to position the cursor on top of a "magic cookie", that to erase standout mode it is instead necessary to use delete and insert line. The ncurses implementation ignores this glitch.

The Beehive Superbee, which is unable to correctly transmit the escape or control C characters, has xsb, indicating that the f1 key is used for escape and f2 for control C. (Only certain Superbees have this problem, depending on the ROM.) Note that in older terminfo versions, this capability was called 'beehive_glitch'; it is now 'no_esc_ctl_c'.

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

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 use can be given with the name of the similar terminal. The capabilities given before use override those in the terminal type invoked by use. A capability can be cancelled by placing xx@ to the left of the capability definition, where xx is the capability. For example, the entry

  2621-nl, smkx@, rmkx@, use=2621,

defines a 2621-nl that does not have the smkx or rmkx capabilities, and 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.

Pitfalls of long entries

Long terminfo entries are unlikely to be a problem; to date, no entry has even approached terminfo's 4K string-table maximum. Unfortunately, the termcap translations are much more strictly limited (to 1K), thus termcap translations of long terminfo entries can cause problems.

The man pages for 4.3BSD and older versions of tgetent(3) instruct the user to allocate a 1K buffer for the termcap entry. The entry gets null-terminated by the termcap library, so that makes the maximum safe length for a termcap entry 1k-1 (1023) bytes. Depending on what the application and the termcap library being used do, and where in the termcap file the terminal type that tgetent(3) is searching for is, several bad things can happen.

Some termcap libraries print a warning message or exit if they find an entry that's longer than 1023 bytes; others do not; others truncate the entries to 1023 bytes. Some application programs allocate more than the recommended 1K for the termcap entry; others do not.

Each termcap entry has two important sizes associated with it: before "tc" expansion, and after "tc" expansion. "tc" is the capability that tacks on another termcap entry to the end of the current one, to add on its capabilities. If a termcap entry does not use the "tc" capability, then of course the two lengths are the same.

The "before tc expansion" length is the most important one, because it affects more than just users of that particular terminal. This is the length of the entry as it exists in /etc/termcap, minus the backslash-newline pairs, which tgetent(3) strips out while reading it. Some termcap libraries also strip off the final newline (GNU termcap does not). Now suppose:

Then tgetent(3) will overwrite memory, perhaps its stack, and probably core dump the program. Programs like tTelnetare particularly vulnerable; modern tTelnetspass along values like the terminal type automatically. The results are almost as undesirable with a termcap library, like SunOS 4.1.3 and Ultrix 4.4, that prints warning messages when it reads an overly long termcap entry. If a termcap library truncates long entries, like OSF/1 3.0, it is immune to dying here but will return incorrect data for the terminal.

The "after tc expansion" length will have a similar effect to the above, but only for people who actually set TERM to that terminal type, since tgetent(3) only does "tc" expansion once it's found the terminal type it was looking for, not while searching.

In summary, a termcap entry that is longer than 1023 bytes can cause (on various combinations of termcap libraries and applications) a core dump, warnings, or incorrect operation. If it's too long even before "tc" expansion, it will have this effect even for users of some other terminal types and users whose TERM variable does not have a termcap entry.

When in -C (translate to termcap) mode, the ncurses implementation of tic(1) issues warning messages when the pre-tc length of a termcap translation is too long. The -c (check) option also checks resolved (after tc expansion) lengths.

Binary Compatibility

It is not wise to count on portability of binary terminfo entries between commercial systems. The problem is that there are at least two versions of terminfo (under HP-UX and AIX) which diverged from System V terminfo after SVr1, and have added extension capabilities to the string table that (in the binary format) collide with System V and XSI Curses extensions.


The %x operator in parameterized strings is unique to the ncurses implementation of tparm (it is required in order to support an unfortunate choice of initc format on the Linux console).

Some SVr4 curses implementations, and all previous to SVr4, do not interpret the %A and %O operators in parameter strings.

SVr4/XPG4 do not specify whether msgr licenses movement while in an alternate-character-set mode (such modes may, among other things, map CR and NL to characters that do not trigger local motions). The ncurses implementation ignores msgr in ALTCHARSET mode. This raises the possibility that an XPG4 implementation making the opposite interpretation may need terminfo entries made for ncurses to have msgr turned off.

The ncurses library handles insert-character and insert-character modes in a slightly non-standard way in order to get better update efficiency. See the Insert/Delete Character subsection above.

The parameter substitutions for set_clock and display_clock are not documented in SVr4 or the XSI Curses standard. They are deduced from the documentation for the AT&T 505 terminal.

Be careful assigning the kmous capability. The ncurses wants to interpret it as KEY_MOUSE, for use by terminals and emulators like xterm that can return mouse-tracking information in the keyboard-input stream.

Different commercial ports of terminfo and curses support different subsets of the XSI Curses standard and (in some cases) different extension sets. Here is a summary, accurate as of October 1995:

SVR4, Solaris, ncurses
These support all SVr4 capabilities.
Supports the SVr4 set, adds one undocumented extended string capability (set_pglen
SVr1, Ultrix
These support a restricted subset of terminfo capabilities. The booleans end with xon_xoff; the numerics with width_status_line; and the strings with prtr_non.
Supports the SVr1 subset, plus the SVr[234] numerics num_labels, label_height, label_width, plus function keys 11 through 63, plus plab_norm, label_on, and label_off, plus some incompatible extensions in the string table.
Supports the SVr1 subset, plus function keys 11 through 63, plus a number of incompatible string table extensions.
Supports both the SVr4 set and the AIX extensions.


The terminfo packages makes use of the following files:

Files containing terminal descriptions.
Canonical list of all terminal entries.