awk

Sample

For this file, logs.txt (from the link above):

07.46.199.184 [28/Sep/2010:04:08:20] "GET /robots.txt HTTP/1.1" 200 0 "msnbot"
123.125.71.19 [28/Sep/2010:04:20:11] "GET / HTTP/1.1" 304 -  "Baiduspider"

$ awk '{print $0}' logs.txt
07.46.199.184 [28/Sep/2010:04:08:20] "GET /robots.txt HTTP/1.1" 200 0 "msnbot"
123.125.71.19 [28/Sep/2010:04:20:11] "GET / HTTP/1.1" 304 -  "Baiduspider"

$ awk '{print $1}' logs.txt
07.46.199.184
123.125.71.19

The special variable, NF, contains the number of fields in the current line:

$ awk '{print $1, $(NF-2) }' logs.txt
07.46.199.184 200
123.125.71.19 304

Another variable is NR, is the row number being currently processed:

$ awk '{print NR ") " $1 " -> " $(NF-2)}' logs.txt
1) 07.46.199.184 -> 200
2) 123.125.71.19 -> 304