Need to peek in a file, and based on what you see,
conditionally
execute a subroutine in an XP batch file? Tired of trying to
figure
out how to stuff a value into an environment variable? 
Instead, use
GNU grep from gnuwin32.sourceforge.net and try:

grep CONDITION filename && goto JUST-DO-IT
rem DON'T DO IT - put commands here to perform if condition
not met
goto OVER-IT
:JUST-DO-IT
put commands here to perform if condition met
:OVER-IT

The portion of the first command line after the &&
only executes if
the grep was successful. If grep found what you were looking
for, the
script branches to JUST-DO-IT. If grep did not find what you
were
looking for, the next line executes, and all lines below it,
until you
hit the second goto which sends you over the the JUST-DO-IT
branch,
and rejoins the script at OVER-IT.