LOOK(1)                                                   LOOK(1)

     NAME
          look - find lines in a sorted list

     SYNOPSIS
          look [ -dfnixtc ] [ string ] [ file ]

     DESCRIPTION
          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 collat-
          ing sequence df.

     FILES
          /lib/words

     SOURCE
          /sys/src/cmd/look.c

     SEE ALSO
          sort(1), grep(1)

     DIAGNOSTICS
          The exit status is ``not found'' if no match is found, and
          ``no dictionary'' if file or the default dictionary cannot
          be opened.