NAME

ttycap − tty capability data base

DESCRIPTION

The ttycap data base gives capabilities of terminals.  Used with ttytype and htmp it allows the use of special terminal features and the adaptation of programs to their input/output environment.  The ttycap file is organized in a manner similar to passwd.  Each line in the file gives a terminal, and then information as to capabilities of that terminal, in fields separated by ‘:’ characters.  The first field gives the two character terminal code used in ttytype to describe the terminal, and then a series of one or more names for this terminal separated by ‘|’ characters.  For example, the entry for an LSI-ADM3A might be: ca|adm3a|3a:0:0:li#24:co#80:cl=^z:nd=^l:up=^k:am:bs:ca Here the internal code for this terminal is seen to be ‘ca’, and it is known as an ‘adm3a’ or a ‘3a’. The next two fields give the modes which are to be set and cleared respectively to return the terminal to a ‘standard’ form. The rest of the fields are indicated by a two-character code, and are of three kinds: numeric valued, string valued, and yes/no capabilities. Numeric valued parameters are given with an ‘#’ and the value, e.g. ‘li#24’. The numeric valued paramters are: linumber of lines (on a CRT screen)
conumber of columns String valued parameters are given with an ‘=’ and then a string up to a ‘:’. The following escapes are recognized in the string:

^lwith l a lower case letter gives control-l
\^gives ^
\:gives :
\Egives an ESCAPE
\\gives a backslash ‘\’
\nnngives character with octal representation nnn
\ngives a newline
\rgives a carriage return
\tgives a tab
\bgives a backspace

In addition, if any line in the file ends with a backslash, then that newline is ignored, effectively continuing the line onto the next. String valued options are: clclear screen sequence
hdhalf-line down sequence
hohome sequence
huhalf-line up sequence
isinitialization sequence (set tabs, etc.) 
iffile name containing initialization sequence
ndnon-destructive space sequence
upup-line (reverse line feed sequence)
aladd new blank line where cursor is (open)
dldelete the line where the cursor is (close)
ceclear to end of line
cdclear to end of display
gugarbage may come up from below when we dl Finally, the following capabilities are recognized: itintelligent terminal
cacursor addressible
ptplotting terminal
amautomatic margins (auto-new-line)
bsbackspace capability
osoverstrike capability
paall characters will print
pttabs will print The set of routines in ttycap (VII) may be used to conveniently deal with the ttycap data. 

LIMITATIONS

A maximum of 512 characters in a single terminal entry are allowed. 

FILES

/etc/ttycapcapability file
/etc/ttytypeterminal type file

SEE ALSO

htmp (V), ttytype (V), sethome (VI), ttytype (VI), htmp (VII), ttycap (VII), typeof (VII)

AUTHOR

William Joy

BUGS

Cursor addressing information should be encoded in a string valued ca option.