man look (Commandes) - look

NAME

look - display lines beginning with a given string

SYNOPSIS

[-df] [-t termchar]string []

DESCRIPTION

The utility displays any lines in file which contain string as a prefix.

If file is not specified, the file /usr/share/dict/words is used, only alphanumeric characters are compared and the case of alphabetic characters is ignored.

Options:

-b
Use a binary search on the given word list. If you are ignoring case with -f or ignoring non-alphanumeric characters with -d , the file must be sorted in the same way. See sort() for more information on sorting files.
-d
Dictionary character set and order, i.e. only alphanumeric characters are compared.
-f
Ignore the case of alphabetic characters.
-t
Specify a string termination character, i.e. only the characters in string up to and including the first occurrence of termchar are compared.

The utility exits 0 if one or more lines were found and displayed, 1 if no lines were found, and >1 if an error occurred.

FILES

/usr/share/dict/words
the dictionary

SEE ALSO

grep(1) ,sort()

COMPATIBILITY

The original manual page stated that tabs and blank characters participated in comparisons when the -d option was specified. This was incorrect and the current man page matches the historic implementation.

uses a linear search by default instead of a binary search, which is what most other implementations use by default.

HISTORY

A utility appeared in