Text Search

UNIX provides a text search command called grep. It searches text for regular expressions. The simplest regular expressions are simply strings of characters. Grep will print out all lines containing the search expression, unless told otherwise:

$cat d
This will be the content of
our new file!
$grep our d
out new file!
$

We can specify multiple files on the command line:

$cat e
This will be the content of
our old file!
$grep our d e
d:our new file!
e:our old file!
$

Or we can count the number of occurrences:

$grep -c our d e
d:1
e:1
$

• Regular Expressions
  • Examples