use constant MTIME    =>    9;    # File modification time

if ((stat("$BulletinSrc"))[MTIME] > (stat("$BulletinPDF"))[MTIME]) {
    $Text .= " PDF is stale             \"$BulletinPDF\"\n";
    $Errors++;
    }
  else {
    $Text .= " PDF is UP-TO-DATE        \"$BulletinPDF\"\n";
    }

##</code><code>##

if (-M "$BulletinSrc" < -M "$BulletinPDF") {
    $Text .= " PDF is stale             \"$BulletinPDF\"\n";
    $Errors++;
    }
  else {
    $Text .= " PDF is UP-TO-DATE        \"$BulletinPDF\"\n";
    }

##</code><code>##

                  Start of program
  TDS             :
  :               :
  V               V
  |<----- A ----->|
  |---------------:
                  :
      TDS         :
      :           :
      V           :
      |-----------:
      |<--- B --->|

   length(A) < length(B) means A is stale
   date(A)   > date(B)   means A is stale  (notice start of program is irrelevant!)

i.e., stat() returns a TDS (time date stamp)
      -M returns a length since the start of the program