STRCAT command

I have a lisp routine that prompts the user to enter a string and displays the default response. But I want to be able to call this lisp from a menu script file and have the "default concatenation" entered or accepted automatically without user input. If I try to simply insert a carraige return in the script file, the variable stays empty as if the user entered no response. How do I force the variable to accept the concatenation through STRCAT?

This is a portion of the lisp file in question...

(While
(Null TmpTop)
(SetQ
TmpTop
(ReadString
T
(StrCat
"\nEnter Vanity description <PY VANITY "
VanSize
" "
VanCol
">: "
)
)
TmpTop
(Cond
((And (= TmpTop "") VanTop) VanTop)
(TmpTop TmpTop)
(T Nil)
)
)
)


After this part, the user will see a prompt at the command line to enter a vanity description. The default response would include preset text ("PY VANITY ") followed by 2 variables defined beforehand ('VANSIZE' and 'VANCOL'). How do I combine all 3 into one new variable without user intervention so that I can call this new variable and insert it into a block attribute as part of a menu script file?

Thanks.

 

You can define a flag value in the button definition and modify the lisp to watch for the flag:

^C^C(setq use_default T) 'YOUR ROUTINE NAME HERE'

In the lisp routine, add an IF statement that checks the status of the use_default variable. If it's T, bypass the user input process. Be sure to set the use_default variable to NIL after it is checked.