Don't you know anything about /filter at all? AT ALL? I find it SO frustrating people don't understand what is truly a basic concept.

Code:
alias filetest {
  if (%filetest.lastfpos !isnum) {
    set %filetest.lastfpos 1
  }
  var %file = $qt($1-), %lines = $lines($1-)
  if (%filetest.lastfpos == %lines) return
  filter -rfk $+(%filetest.lastfpos,-,%lines) %file _filetest
  set %filetest.lastfpos %lines
}
alias -l _filetest {
  if ($1-) echo -a $1-
}


Consistently performs twice as fast as the file handling method smile
Oh yeah, less code too.