look - find lines in a sorted list
look [ -dfnixtc ] [ string ] [
file ]
Look consults a sorted file and prints all lines
that begin with string. It uses binary search.
The following options are recognized. Options dfnt affect
comparisons as in sort(1).
- -i
- Interactive. There is no string argument; instead look takes
lines from the standard input as strings to be looked up.
- -x
- Exact. Print only lines of the file whose key matches string
exactly.
- -d
- `Directory' order: only letters, digits, tabs and blanks participate in
comparisons.
- -f
- Fold. Upper case letters compare equal to lower case.
- -n
- Numeric comparison with initial string of digits, optional minus sign, and
optional decimal point.
- -t[c]
- Character c terminates the sort key in the file. By default,
tab terminates the key. If c is missing the entire line comprises
the key.
If no file is specified, /lib/words is assumed, with
collating sequence df.
The exit status is ``not found'' if no match is found, and
``no dictionary'' if file or the default dictionary cannot be
opened.