TANDBERG Security Camera 180, Regular Expression Reference, Overview Common Regular Expressions

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Regular Expression Reference

TANDBERG VIDEO COMMUNICATIONS SERVER ADMINISTRATOR GUIDE

Overview Common Regular Expressions

Regular expressions can be used in conjunction with a number of VCS features such as alias transformations, zone transformations, CPL policy and ENUM. The VCS uses POSIX format regular expression syntax.

The table opposite provides a list of commonly used special characters in regular expression syntax. This is only a subset of the full range of expressions available. For a detailed description of regular expression syntax see the publication Mastering Regular Expressions [9].

Character Description Example

.Matches any single character.

* Matches 0 or more repetitions of the previous match. .* will match against any sequence of characters.

+Matches 1 or more repetitions of the previous match.

\Escapes a regular expression special character.

\d	Matches any decimal digit, i.e. 0-9.
[...]	Matches a set of characters. Each character in the set	[a-z]will match against any lower case alphabetical character.
	can be specified individually, or a range can be specified	[a-zA-Z]will match against any alphabetical character.
	by giving the first character in the range followed by the	[0-9#*]will match against any single E.164 character - the E.164 character
	- character and then the last character in the range.
		set is made up of the digits 0-9plus the hash key (#) and the asterisk key
	You can not use special characters within the [] - they
		( ).
	will be taken literally.	*
(...)	Groups a set of matching characters together. Groups	A regular expression can be constructed to transform a URI containing a
	can then be referenced in order using the characters \1,	user’s full name to a URI based on their initials.
	\2, etc. as part of a replace string.	The regular expression (.).* _ (.).*(@example.com) would match against
		the user john _ smith@example.com and with a replace string of \1\2\3
		would transform it to js@example.com.
	Matches against one expression or an alternate	.*@example.(netcom) will match against any URI for the domain
	expression.	example.com or the domain example.net.

^Signifies the start of a line.

When used immediately after an opening brace, negates [^abc] matches any single character that is NOT one of a, b or c. the character set inside the brace.

$	Signifies the end of a line.	^\d\d\d$ will match any string that is exactly 3 digits long.
(?!...)	Negative lookahead. Defines a subexpression that must	(?!.*@tandberg.net$).* will match any string that does not end with @
	not be present in order for there to be a match.	tandberg.net.

For an example of regular expression usage, see the section CPL Examples.

Introduction	Getting Started	Overview and	System	VCS	Zones and	Call	Bandwidth	Firewall	Maintenance	Appendices
		Status	Configuration	Configuration	Neighbors	Processing	Control	Traversal
D14049.03					180
MAY 2008