---
name: "std::chrono::::system_clock"
section: "3cxx"
platform: "linux"
package: "libstdc++-11-doc"
version: "11.3.0-12"
release: "Debian 12 (Bookworm)"
platforms: ["linux"]
url: "https://new.carta.tech/std::chrono::::system_clock"
---

# std::chrono::::system\_clock(3cxx)

System clock.

## NAME

std::chrono::system\_clock - System clock.

## SYNOPSIS

### Public Types

typedef **chrono::nanoseconds** **duration**\
 typedef duration::period **period**\
 typedef duration::rep **rep**\
 typedef **chrono::time\_point**\< **system\_clock**, **duration** \> **time\_point**\

### Static Public Member Functions

static **time\_point** **from\_time\_t** (std::time\_t \_\_t) noexcept\
 static **time\_point** **now** () noexcept\
 static std::time\_t **to\_time\_t** (const **time\_point** &\_\_t) noexcept\

### Static Public Attributes

static constexpr bool **is\_steady**\

## Detailed Description

System clock.

Time returned represents wall time from the system-wide clock.

Definition at line **1125** of file **chrono**.

## Member Typedef Documentation

### typedef chrono::nanoseconds std::chrono::system\_clock::duration

Definition at line **1127** of file **chrono**.

### typedef duration::period std::chrono::system\_clock::period

Definition at line **1129** of file **chrono**.

### typedef duration::rep std::chrono::system\_clock::rep

Definition at line **1128** of file **chrono**.

### typedef chrono::time\_point\<system\_clock, duration\> std::chrono::system\_clock::time\_point

Definition at line **1130** of file **chrono**.

## Member Function Documentation

### static time\_point std::chrono::system\_clock::from\_time\_t (std::time\_t \_\_t)` [inline]`, ` [static]`, ` [noexcept]`

Definition at line **1150** of file **chrono**.

### static std::time\_t std::chrono::system\_clock::to\_time\_t (const time\_point & \_\_t)` [inline]`, ` [static]`, ` [noexcept]`

Definition at line **1143** of file **chrono**.

## Member Data Documentation

### constexpr bool std::chrono::system\_clock::is\_steady` [static]`, ` [constexpr]`

Definition at line **1136** of file **chrono**.

## Author

Generated automatically by Doxygen for libstdc++ from the source code.