in reply to Trim Phone Numbers
perl -e 'print qq!$_\n! for grep {length} map {s/.*(\d{7})/*$1/ ? $_ : + q!!} @ARGV;' 1234567890 1234567 1234567890123 wibble 123 [download]
Prints:
*4567890 *1234567 *7890123 [download]