TAPSET::REGEX(3stap) TAPSET::REGEX(3stap)

# [NAME](#NAME)

tapset::regex - systemtap regex tapset

# [DESCRIPTION](#DESCRIPTION)

[**matched\_str**](#matched_str)

Return the last matched string.

See [*function::matched\_str*(3stap)](/man/enterprise-packages/systemtap/function::matched_str.3stap)  
for details.

[**matched**](#matched)

Return a given matched subexpression.

See [*function::matched*(3stap)](/man/enterprise-packages/systemtap/function::matched.3stap)  
for details.

[**ngroups**](#ngroups)

Number of subexpressions in the last match.

See [*function::ngroups*(3stap)](/man/enterprise-packages/systemtap/function::ngroups.3stap)  
for details.

# [SEE ALSO](#SEE_ALSO)

[*function::matched\_str*(3stap)](/man/enterprise-packages/systemtap/function::matched_str.3stap), [*function::matched*(3stap)](/man/enterprise-packages/systemtap/function::matched.3stap), [*function::ngroups*(3stap)](/man/enterprise-packages/systemtap/function::ngroups.3stap), [*stap*(1)](/man/enterprise-packages/systemtap/stap.1), [*stapprobes*(3stap)](/man/enterprise-packages/systemtap/stapprobes.3stap)

September 2026 SystemTap Tapset Reference

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Document: tapset::regex(3stap) from systemtap 5.6-r0 (Chainguard OS)
Source: https://sourceware.org/git/systemtap.git