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look - Unix, Linux Command
NAME
look - display lines beginning with a given string.
SYNOPSIS
DESCRIPTION
look utility displays any lines in file which contain string as a prefix. As look performs a binary search, the lines in file must be sorted. if file is not specified, the file /usr/share/dict/words is used, only alphanumeric characters are com-pared compared pared and the case of alphabetic characters is ignored. 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.
Options
| Tag | Description |
|---|---|
| -a, --alternative | Use the alternative dictionary file. |
| -d, --alphanum | 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. |
| -f, --ignore-case | 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. |
| -V, --version | Display version information and exit. |
| -h, --help | Display help text and exit. |
EXAMPLES
Example-1:
Check spelling using look command:
For example, if you are not sure whether ‘exclaimation’ or ‘exclamation’ is the correct spelling, you can use look command with first few characters of the word.
$ look excla
output:
exclaim exclaimed exclaiming exclaims exclamation exclamation's exclamations exclamatory This displays the word that starts with the given prefix from file /usr/share/dict/words.
Example-2:
To Check spelling for a word from user defined file:
When you want to know the spelling of a word which has the prefix ‘excl’.
$ look excl myfile
output:
exclaimed exclamation This displays the word that starts with the given prefix from file myfile.
Example-3:
Ignore case while searching for spelling of word:
When you want to know the spelling of a word which has the prefix ‘excl’.
$ look excl myfile
output:
exclaimed exclamation EXCLAMATORY This displays the word that starts with the given prefix from file myfile by ignoring the case.