Open System Services System Calls Reference Manual (G06.25+, H06.03+)

Files termcap(4)
Special strings to go to a position in the status line and to return from the status line can be given
as the ts and fs capabilities. (Note that fs must leave the cursor position in the same place that it
was before ts. If necessary, the strings from the sc and rc capabilities can be included in ts and
fs to get this effect.) The ts capability 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 es
capability can be given. A string that turns off the status line (or otherwise erases its contents)
should be indicated by the ds capability.
The status line is normally assumed to be the same width as the rest of the screen; that is, the
value indicated in the co capability. 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 ws capability.
If the terminal can move up or down half a line, this can be indicated with the hu (half-line up)
and hd (half-line down) capabilities. This feature is primarily useful for superscripts and sub-
scripts on hard-copy terminals. If a hard-copy terminal can eject to the next page (formfeed),
indicate this with the ff capability (usually ˆL).
If the terminal has a settable command character, such as the Tektronix 4025 terminal, indicate
this with the CC capability. A prototype command character is chosen that is used in all capabil-
ities. This character is given in the CC capability to identify it. The following convention is
supported on some UNIX systems: the environment is searched for a CC variable, and if found,
all occurrences of the prototype character are replaced by the character in the environment vari-
able. Do not use the CC environment variable in this way; it conflicts with the make command.
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 applications can
explain that they do not know how to talk to the terminal. (This capability does not apply to vir-
tual terminal descriptions for which the escape sequences are known.)
If the terminal uses xoff/xon (DC3/DC1) handshaking for flow control, indicate this with the xo
capability. Padding information should still be included so that routines can make better deci-
sions about costs, but actual pad characters are not transmitted.
If the terminal has a meta key that acts as a shift key by setting the 8th bit of any character
transmitted, then this fact can be indicated with the km capability. Otherwise, software assumes
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 by the mm and mo capabilities.
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 the lm capability. An explicit value of 0 (zero) indicates that
the number of lines is not fixed but 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 termi-
nal number can be given by the vt capability.
Media copy strings that control an auxiliary printer connected to the terminal can be given with
the following capabilities:
ps Prints the contents of the screen
pf Turns off the printer
po Turns on the printer
When the printer is on, all text sent to the terminal is sent to the printer. It is undefined whether
the text is also displayed on the terminal screen when the printer is on. A variation, the pO capa-
bility, 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
527186-003 Hewlett-Packard Company 11−49