POSIX Extended Regular Expression Syntax (Quick Reference)

This article lays out POSIX Extended Regular Expression syntax implemented by ThousandEyes for page content verification in HTTP Server tests. For those wanting a more comprehensive article on this regular expression syntax, along with testing and troubleshooting guidelines, see this article.

Single-Character Expressions

.	matches any character
[x-y]	matches any character found in the range of x-y
[abcdefg]	matches any character found in the bracketed list
\d	matches any digit character (0-9)
\w	matches any alphanumeric character, including underscore
\s	matches any whitespace character
	matches a newline character
x|y	matches x OR y
\	escape character
\W	non-alphanumeric character
\D	non-digit character
\S	non-whitespace character
[^abcdefg]	matches any character NOT found in the bracketed list

Repeaters

{n}	previous expression matches exactly n times
{n,}	previous expression matches at least n times
{,m}	previous expression matches at most m times
{n,m}	previous expression matches between n and m times (inclusive)
*	previous expression matches 0 or more times
?	previous expression matches 0 or 1 times
+	previous expression matches 1 or more times

Patterns

(	start of pattern
)	end of pattern

Boundaries

^	beginning of line (only valid when used at the beginning of a pattern)
$	end of line (only valid when used at the end of a pattern)
\`	beginning of input (start of the page)
'	end of input (end of the page)
\b	word boundary