Thanks in no small part to several of the monks here, I have used the following routine to deal with some "flag bytes" in an IBM Mainframe file. A record is read into $inBuf, then fields are parsed out according to format.

...
      @Ind0 = BreakOut(substr($inBuf,6,1));  
      $Flag1= $Ind0[0];
      ...
      $Flag7= $Ind0[7];
...
sub BreakOut {
# Convert a single byte into an array of 8 1-bit flags
# represented by a Y if ON, or an N if OFF.
  my $byte = shift;
  my @flag, $i;
  for ($i=0;$i<8;$i++) {
    if (vec($byte,$i,1)) {
       $flag[7-$i] = "Y";
    } else {
       $flag[7-$i] = "N";
    } # End If vec
  } # End For
  return @flag;
} # End Sub BreakOut
[download]