Status Lines
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, into which one can
cursor address normally (such as the Heathkit H19's 25th line, or
the 24th line of a VT100 which is set to a 23-line scrolling region),
the capability hs should be given. Special strings
that go to a given column of the status line and return from the status
line can be given as tsl and fsl.
(fsl must leave the cursor position in the same
place it was before tsl. If necessary, the sc and rc strings can be included
in tsl and fsl to get
this effect.) The capability tsl takes one argument,
which is the column number of the status line the cursor is to be
moved to.
If escape sequences and other special commands, such as tab, work while in the status line, the flag eslok can be given. A string which turns off the status line (or otherwise erases its contents) should be given as dsl. If the terminal has commands to save and restore the position of the cursor, give them as sc and rc. The status line is normally assumed to be the same width as the rest of the screen (that is, cols). If the status line is a different width (possibly because the terminal does not allow an entire line to be loaded) the width, in columns, can be indicated with the numeric argument wsl.