look - display lines beginning with a given string
look [options] string [file]
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 characters is ignored.
Use the alternative dictionary file.
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.
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
characters in string up to and including the first occurrence of
character are compared.
Display version information and exit.
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.
Path to a dictionary file. The environment variable has
greater priority than the dictionary path defined in FILES segment.
the alternative dictionary
The look utility appeared in Version 7 AT&T Unix.
sort -d /etc/passwd -o /tmp/look.dict
look -t: root:foobar /tmp/look.dict