Name

look

Synopsis

    look [options] string [file]

Look through a sorted file and print all lines that begin with string. string may be up to 256 characters long. This program is potentially faster than fgrep because it relies on the file being already sorted, and can thus do a binary search through the file, instead of reading it sequentially from beginning to end.

With no file, look searches /usr/share/lib/dict/words (the spelling dictionary) with options -df.

Common Options

-d

Use dictionary order. Only letters, digits, space, and tab are used in comparisons.

-f

Fold case; ignore case distinctions in comparisons.

-t char

Use char as the termination character, i.e., ignore all characters to the right of char.

GNU/Linux Option

-a

Use alternate dictionary /usr/share/dict/web2.

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