REGULAR EXPRESSIONS
Regular expressions
are a form of pattern matching syntax which many commands use. (e.g.
grep, sed
)
They are very flexible and not quickly learnt.
Some basic forms are easy to learn and very useful.
Not
the same as shell wildmasks, although some are similar.
Special characters used in regular expressions include:
.
matches any one character
*
matches zero or more of the last character
.*
matches any string
[ ]
matches any character in the range
^
represents the start of the line
$
represents the end of the line
[^ ]
matches any character
not
in the range
