Cisco ASR 5000 Series Administration Manual page 23

Enhanced Charging Service Overview
Regex Character Description
\r Match the carriage return (ASCII 13) character
\t Match the tab (ASCII 9) character
\v Match the vertical tab (ASCII 11) character
\0 Match the null (ASCII 0) character
\\ Match the backslash character
Bracketed range Match any single character from the range
[0-9]
A leading ^ in a Do not match any in the range. All other characters represent themselves.
range
.\x## Any ASCII character as specified in two-digit hex notation.
For example, \x5A yields a "Z".
| Specify OR regular expression operator
For example, if you want to match the string pqr OR xyz, you must configure it as:
http host regex "pqr|xyz"
The following are some examples of the use of regex characters in rule expressions:
 The following command specifies a regex rule expression using the regex character * (asterisk) to match any of
the following or similar values in the HTTP Host request-header field: host1, host101, host23w01.
http host regex "host*1"
 The following command specifies a regex rule expression using the regex character + (plus) to match any of the
following or similar values in the HTTP Host request-header field: host1, host101, host23w01.
http host regex "host+"
 The following command specifies a regex rule expression using the regex character \077 (?) to match any of the
following or similar values in the HTTP Host request-header field: host101.
http host regex "hos\077t101"
 The following command specifies a regex rule expression using the regex character \ (escaped character) to
match the following value in the HTTP Host request-header field: host?example.
http host regex "host\\\077example"
The first two \ form an escape sequence and \077 is converted to ?. The \? is converted to ? as a character and
not a place-holder.
 The following command specifies a regex rule expression using the regex character \ (escaped backslash
character) to match the following value in the HTTP Host request-header field: host*01.
http host regex "host\\*01"
The first \ is used as an escape sequence for the second \.
Important:
When using the regex operator "|" in regex expressions, always wrap the
string in double quotes.
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Cisco ASR 5x00 Enhanced Charging Services Administration Guide ▄
Basic Features and Functionality ▀
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