POSIX Extended Regular Expression Syntax (quick reference)

Last updated: Mon Feb 04 23:43:35 GMT 2019

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, please 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 
\n 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)
\bword boundary