2011

AutoLISP provides two file formats for applications:
■ Reading an LSP file (.lsp)—an ASCII text file that contains AutoLISP program
code.
■ Reading an FAS file (.fas)—a binary, compiled version of a single LSP
program file.
NOTE Like-named AutoLISP application files are loaded based on their Modified
time stamp; the LSP or FAS file with the most recent time stamp is loaded unless
you specify the full file name (including the file name extension).
Because AutoCAD for Mac can read AutoLISP code directly, no compiling is
required. This makes AutoLISP an easy language to experiment with, regardless
of your programming experience.
Even if you are not interested in writing AutoLISP applications, your AutoCAD
for Mac package includes many useful routines. Routines are also available as
shareware through third-party developers. Knowing how to load and use these
routines can enhance your productivity.
NOTE When command input comes from the AutoLISP command function, the
settings of the PICKADD and PICKAUTO system variables are assumed to be 1 and
0, respectively. This preserves compatibility with previous releases of AutoCAD for
Mac and makes customization easier (because you don't have to check the settings
of these variables).
For information about AutoLISP programming, see the AutoLISP Developer's
Guide, and for information about AutoLISP, see the AutoLISP Reference in the
Help system.
Quick Reference
System Variables
PICKADD
Controls whether subsequent selections replace the current selection set or
add to it.
PICKAUTO
Controls automatic windowing at the Select Objects prompt.
94 | Chapter 7 Introduction to Programming Interfaces