look - find lines in a sorted list look [ -df ] string [ file ] Look consults a sorted file and prints all lines that begin with string . It uses binary search. The options -d and -f affect comparisons as in sort (1). If no file is specified, /usr/lib/dict/words is assumed with collating sequence -df .

5 -d Dictionary order: compare letters, digits and whitespace.

5 -f Fold. Upper case letters compare equal to lower case.

25 /usr/lib/dict/words Sorted list of English words.

sort (1), spell (1). Kees J. Bot (kjb@cs.vu.nl)