Using the in and do keywords
In and do are not parameters, but they are required in the for command. If you omit either of these keywords, Windows NT displays an error
Using the replaceable variable
To avoid confusion with the batch parameters %0 through %9, you can use any character for variable except the numerals 0 through 9. For simple batch programs, a single
character such as %%f may be all that is necessary.
You can use multiple values for variable in complex batch programs to distinguish different replaceable variables.
Specifying a group of files
The set parameter can represent a single group of files or several groups of
files. You can use wildcards (* and ?) to specify a file set. The following are
valid file sets:
(*.doc *.txt *.me)
(jan*.doc jan*.rpt feb*.doc feb*.rpt)
When you use the for command, the first value in set replaces %%variable (or %variable) and Windows NT carries out the specified command in order to process this
value; this continues until Windows NT has processed all the files (or groups of
files) that correspond to the value (or values) in set.
More Information About For