Cisco Sx350, Cli Manual

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Introduction
Cisco Sx350 Ph. 2.2.5 Devices - Command Line Interface Reference Guide 44
1
Multiple-Character Patterns
When creating regular expressions, you can also specify a pattern containing
multiple characters. You create multiple-character regular expressions by joining
letters, digits, or keyboard characters that do not have special meaning. For
example, a4% is a multiple-character regular expression.
With multiple-character patterns, order is important. The regular expression a4%
matches the character a followed by a 4 followed by a % sign. If the string does
not have a4%, in that order, pattern matching fails. The multiple-character regular
expression a. uses the special meaning of the period character to match the letter
a followed by any single character. With this example, the strings ab, a!, or a2 are
all valid matches for the regular expression.
You can remove the special meaning of the period character by inserting a
backslash before it. For example, when the expression a\. is used in the command
syntax, only the string a. will be matched.
You can create a multiple-character regular expression containing all letters, all
digits, all keyboard characters, or a combination of letters, digits, and other
keyboard characters. For example, telebit 3107 v32bis is a valid regular
expression.
Multipliers
You can create more complex regular expressions that instruct the system to
match multiple occurrences of a specified regular expression. To do so, use some
special characters with your single-character and multiple-character patterns.
Table 1 lists the special characters that specify multiples of a regular expression.
The following example matches any number of occurrences of the letter a,
including none:
a*
Table 1: Special Characters Used as Multipliers
Character
Description
*
Matches 0 or more single-character or
multiple-character patterns.
+
Matches 1 or more single-character or
multiple-character patterns.
? Matches 0 or 1 occurrences of a single-character or
multiple-character pattern.