tfscan

[ableasby at hgmp.mrc.ac.uk]

There are replacement files for tfscan.c and tfscan.acd in the
directory:
   ftp://ftp.uk.embnet.org/pub/EMBOSS/patchfiles/

which will allow you to add (e.g.)  -minlength 3  to the
command line.

HTH

Alan