HVP Horizontal and Vertical Position

Move the cursor to line Pl, column Pc, exactly as CUP does: both count from 1, either can be left out, a 0 is taken as 1, a position past the edge is clamped to it, and with origin mode on the position counts from the margins.

The two exist side by side for a historical reason. In ECMA-48, HVP moves the data position while CUP moves the presentation position, a distinction that matters to a device where the two can differ. A terminal has only one cursor. DEC STD 070 defines HVP by calling CUP’s own algorithm, and keeps it only for compatibility with printing terminals, telling software to use CUP instead. The VT510 manual says the same.

Validation

HVP-1: To a position

\e[2;3f
X

|_____|
|__X__|
|_____|

HVP-2: Defaults

\e[3;3f
\e[f      # both left out
A
\e[2f     # column left out
B
\e[;4f    # line left out
C
\e[0;0f   # zero is one
D

|D__C_|
|B____|
|_____|

HVP-3: Clamped to the screen

\e[999;999f
X

|_____|
|_____|
|____X|

HVP-4: With origin mode

\e[2;3r   # region is lines 2 and 3
\e[?6h    # origin mode
\e[1;1f   # the top of the region
A
\e[9;1f   # clamped to the bottom of the region
B

|_____|
|A____|
|B____|
|_____|