How to sort on exactly one field only

[Doug Gwyn]

In article <1757 at b15.INGR.COM> rob at b15.INGR.COM (Rob Lemley) writes:
>The man page clearly states that you cannot cause sort to ignore a field
>or preserve relative line ordering.

"sort" does ignore non-key fields except when keys compare equal.
To obtain a stable sort, add line numbers, sort on the keys you
wanted followed by the line numbers as an additional key, then
strip off the line numbers.