z/OS V1R9.0 UNIX System Services Command ... - Christian Grothoff

sort
Sorting Keys
By default, sort examines entire input records to determine ordering. By specifying
sorting keys on the command line, you can tell sort to restrict its attention to one or
more parts of each record.
You can indicate the start of a sorting key with:
-k m[.n][options]
where m and the optional n are positive integers. You can choose options from the
set bdfiMnr (described previously) to specify the way in which sort does
comparisons for that sorting key. Ordering options set for a key override global
ordering options. If you do not specify any options for the key, the global ordering
options are used.
The number m specifies which field in the input record contains the start of the
sorting key. The character given with the –t option separates input fields; if this
option is not specified, spaces or tabs separate the fields. The resulting sort key is
from the mth field to the end of the record. The number n specifies which character
in the mth field marks the start of the sorting key; if you do not specify n, the sorting
key starts at the first character of the mth field.
If an ending position for a key is not specified, the sorting key extends from the
starting position to the end of the input record. You can also specify an ending
position for a key, with:
-k m[.n][options],
p[.q][options]
where p and q are positive integers, indicating that the sort key ends with the with
qth character of the pth field. If you do not specify q or if you specify a value of 0
for q, the sorting key ends at the last character of the pth field. For example:
-k 2.3,4.6
defines a sorting key that extends from the third character of the second field to the
sixth character of the fourth field. The b option applies only the key start or key end
for which it is specified;
-k 2
defines a sorting key that extends from the first character of the second field to the
end of the record;
-k2 2
defines a sorting key that extends from the first character of the second field to the
last character of the second field.
sort also supports a historical method of defining the sorting key. Using this
method, you indicate the start of the sorting key with:
+m[.n][options]
which is equivalent to:
–k m+1[.n+1][options]
You can also indicate the end of a sorting key with:
–p[.q][options]
590 z/OS V1R9.0 UNIX System Services Command Reference