2011

Command Search Procedure
When you enter a command, AutoCAD for Mac goes through a series of steps
to evaluate the validity of the command name. A command can be a built-in
command or system variable, an external command or alias defined in the
acad.pgp file, or a user-defined AutoLISP command. Commands can also be
defined by ObjectARX applications or a device driver command. You can enter
a command on the command prompt or choose a command from the
appropriate menu. Commands can also be entered from a script file or by an
AutoLISP or ObjectARX application.
The following list describes the search order AutoCAD for Mac uses to validate
a command name.
1 If the input is a null response (Spacebar or Enter), AutoCAD for Mac uses
the name of the last command issued.
2 AutoCAD for Mac checks the command name against the list of built-in
commands. If the command is in the list and is not preceded by a period
(.), AutoCAD for Mac then checks the command against a list of undefined
commands. If the command is undefined, the search continues.
Otherwise, the command is run, unless another reason prevents it from
doing so. Running it transparently or in Perspective mode might be
impossible.
3 AutoCAD for Mac checks the command name against the names of
commands defined by a device driver, and then by those defined by the
display driver.
4 AutoCAD for Mac checks the command name against the external
commands defined in the program parameters file (acad.pgp). If the
command name corresponds to a defined external command, that
command runs, and the search is complete.
5 AutoCAD for Mac checks the command name against the list of
commands defined by AutoLISP or ObjectARX applications. At this point,
an autoloaded command is loaded.
6 AutoCAD for Mac checks the command name against the list of system
variables. If the command name is in the list, AutoCAD for Mac executes
the SETVAR command, using the input as the variable name.
7 If the command name corresponds to a command alias defined in the
program parameters file, AutoCAD for Mac uses the expanded command
name and continues the search, starting a new search against the list of
built-in commands.
Overview of File Organization | 5