LOOK(1) User Commands LOOK(1)
NAME
look - display lines beginning with a given string
SYNOPSIS
look [options] string [file]
DESCRIPTION
The look utility displays any lines in file which contain string. As
look performs a binary search, the lines in file must be sorted (where
sort(1) was given the same options -d and/or -f that look is invoked
with).
If file is not specified, the file /usr/share/dict/words is used, only
alphanumeric characters are compared and the case of alphabetic charac-
ters is ignored.
OPTIONS
-a, --alternative
Use the alternative dictionary file.
-d, --alphanum
Use normal dictionary character set and order, i.e., only blanks
and alphanumeric characters are compared. This is on by default
if no file is specified.
Note that blanks have been added to dictionary character set for
compatibility with sort -d command since version 2.28.
-f, --ignore-case
Ignore the case of alphabetic characters. This is on by default
if no file is specified.
-t, --terminate character
Specify a string termination character, i.e., only the charac-
ters in string up to and including the first occurrence of char-
acter are compared.
-V, --version
Display version information and exit.
-h, --help
Display help text and exit.
The look utility exits 0 if one or more lines were found and displayed,
1 if no lines were found, and >1 if an error occurred.
EXAMPLE
sort -d /etc/passwd -o /tmp/look.dict
look -t: root:foobar /tmp/look.dict
ENVIRONMENT
WORDLIST
Path to a dictionary file. The environment variable has greater
priority than the dictionary path defined in FILES segment.
FILES
/usr/share/dict/words
the dictionary
/usr/share/dict/web2
the alternative dictionary
SEE ALSO
grep(1), sort(1)
HISTORY
The look utility appeared in Version 7 AT&T Unix.
AVAILABILITY
The look command is part of the util-linux package and is available
from https://www.kernel.org/pub/linux/utils/util-linux/.
util-linux June 2011 LOOK(1)