std::system_error (3) - Linux Manuals

std::system_error: std::system_error


std::system_error - std::system_error


Defined in header <system_error>
class system_error; (since C++11)

std::system_error is the type of the exception thrown by various library functions (typically the functions that interface with the OS facilities, e.g. the constructor of std::thread) when the exception has an associated std::error_code, which may be reported.
 std-system error-inheritance.svg
Inheritance diagram

Member functions

              constructs the system_error object
constructor (public member function)
              returns error code
code (public member function)

what returns explanatory string
              (virtual public member function)

Inherited from std::exception

Member functions

destructor destroys the exception object
             (virtual public member function of std::exception)

what returns an explanatory string
             (virtual public member function of std::exception)


// Run this code

  #include <thread>
  #include <iostream>
  #include <system_error>

  int main()
      try {
          std::thread().detach(); // attempt to detach a non-thread
      } catch(const std::system_error& e) {
          std::cout << "Caught system_error with code " << e.code()
                    << " meaning " << e.what() << '\n';


  Caught system_error with code generic:22 meaning Invalid argument