"thinktwice" <memorialday******.com> wrote in message
news:eb8dc0df-d296-40db-9274-4fb5bdb44a28@f24g2000prh.googlegroups.com...
> //file 1.bat
> @call file3.bat
>
> //file 2.bat
> @call file1.bat
> @call file3.bat
>
> //file3.bat
> if variable_a has been defined (goto eof ) else (define variable_a)
>
> i don't want to run the same batch file more than once.

if defined variable_a echo the value of variable_a is %variable_a%