| .TH LOOK 1 | |
| .SH NAME | |
| look \- find lines in a sorted list | |
| .SH SYNOPSIS | |
| .B look | |
| [ | |
| .BI -dfnixt c | |
| ] | |
| [ | |
| .I string | |
| ] | |
| [ | |
| .I file | |
| ] | |
| .SH DESCRIPTION | |
| .I Look | |
| consults a sorted | |
| .I file | |
| and prints all lines that begin with | |
| .IR string . | |
| It uses binary search. | |
| .PP | |
| The following options are recognized. | |
| Options | |
| .B dfnt | |
| affect comparisons as in | |
| .IR sort (1). | |
| .TP | |
| .B -i | |
| Interactive. | |
| There is no | |
| .I string | |
| argument; instead | |
| .I look | |
| takes lines from the standard input as strings to be looked up. | |
| .TP | |
| .B -x | |
| Exact. | |
| Print only lines of the file whose key matches | |
| .I string | |
| exactly. | |
| .TP | |
| .B -d | |
| `Directory' order: | |
| only letters, digits, | |
| tabs and blanks participate in comparisons. | |
| .TP | |
| .B -f | |
| Fold. | |
| Upper case letters compare equal to lower case. | |
| .TP | |
| .B -n | |
| Numeric comparison with initial string of digits, optional minus sign, | |
| and optional decimal point. | |
| .TP | |
| .BR -t [ \f2c\f1 ] | |
| Character | |
| .I c | |
| terminates the sort key in the | |
| .IR file . | |
| By default, tab terminates the key. If | |
| .I c | |
| is missing the entire line comprises the key. | |
| .PP | |
| If no | |
| .I file | |
| is specified, | |
| .B /lib/words | |
| is assumed, with collating sequence | |
| .BR df . | |
| .SH FILES | |
| .B /lib/words | |
| .SH SOURCE | |
| .B \*9/src/cmd/look.c | |
| .SH "SEE ALSO" | |
| .IR sort (1), | |
| .IR grep (1) | |
| .SH DIAGNOSTICS | |
| The exit status is | |
| .RB `` "not found" '' | |
| if no match is found, and | |
| .RB `` "no dictionary" '' | |
| if | |
| .I file | |
| or the default dictionary cannot be opened. |