@rem = '--*-Perl-*--
@echo off
perl -x "%~dpnx0" %*
goto endofperl
@rem ';
#!/usr/local/bin/perl -w
#line 8

my $line = $ENV{"LOGFOO"};
my $start=0;

while (<>) {
  chomp;
  $start=1 if m|^:endofperl|;
  if ( $start and m|^::| ) {
    exit(0) if $_ eq '::'.$line;
  }
}
exit(1); # Not found
__END__
Code to invoke is thus:
 set logfoo="%~dpnx0" %*
 call logfoo "%~dpnx0"
 if errorlevel 1 echo ::"%~dpnx0" %*>> "%~dpnx0"
 set logfoo=
 ... rest of batch script ...

:endofperl