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 collating 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. 

Plan 9  —  April 17, 2005