Function Entry: GETCORNER

getcorner

Function

(getcorner pt [msg])

• pt: first corner point
• msg: optional prompt string

Autodesk documents pt as a 2D or 3D point.

Prompts the user for the opposite corner of a rectangular area.

Point list or nil.

• prompts the user
• consumes interactive input

• AutoCAD 2026: documented (per Autodesk reference page).
• BricsCAD V26: presumed compatible (no contradicting page found).
• Status: AutoCAD documented; BricsCAD presumed-both pending Phase 4 verification.

• [About The Getxxx Functions (AutoLISP)](https://help.autodesk.com/cloudhelp/2026/CHS/AutoCAD-MAC-AutoLisp/files/GUID-5D9F55C4-97FE-4FF1-81D2-C9F5905C2E25.htm)
• [User Input Functions Reference (AutoLISP)](https://help.autodesk.com/cloudhelp/2026/KOR/AutoCAD-LT-AutoLISP-Reference/files/GUID-49DBE7DD-D1D2-4B3A-9718-E3F4E2FD5E81.htm)

• Autodesk documents that getcorner obtains the opposite corner of a box.
• Autodesk documents that it honors keywords established by initget.

clautolisp implementation deviation — not part of the normative specification above. AutoCAD and BricsCAD collect this corner through the graphical drawing editor, rubber-banding a box from pt under pointer control (implicitly a GUI). clautolisp has no drawing editor — it writes the prompt to the standard output and reads the answer as one line of text from the standard input (a TUI interaction). Interactively this is the REPL's terminal; for scripted, deterministic runs it is the file attached with --mock-input. A live CAD host, when connected, restores the native GUI behavior. On the TUI the opposite corner is typed as whitespace-separated coordinates — X Y or X Y Z (Z defaults to 0.0); the base point pt is accepted but no box is rubber-banded. Invalid input returns nil rather than re-prompting.