std::system_error::system_error (3) Linux Manual Page
std::system_error::system_error – std::system_error::system_error
Synopsis
system_error(std::error_code ec);
(1)(since C++ 11)
system_error(std::error_code ec, const std::string &what_arg);
(2)(since C++ 11)
system_error(std::error_code ec, const char *what_arg);
(2)(since C++ 11)
system_error(int ev, const std::error_category &ecat);
(3)(since C++ 11)
system_error(int ev, const std::error_category &ecat, (4)(since C++ 11)
const std::string &what_arg);
system_error(int ev, const std::error_category &ecat, (4)(since C++ 11)
const char *what_arg);Constructs new system error object.
1) Constructs with error code ec
2) Constructs with error code ec and explanation string what_arg. The string returned by what() is guaranteed to contain what_arg as a substring.
3) Constructs with underlying error code ev and associated error category ecat.
4) Constructs with underlying error code ev, associated error category ecat and explanatory string what_arg. The string returned by what() is guaranteed to contain what_arg as a substring.
Parameters
ec – error code
ev – underlying error code in the enumeration associated with ecat
ecat – the category of error
what_arg – explanatory string
Example
Demonstrates how to create a system_error exception from an errno value.
// Run this code
#include <iostream>
#include <system_error>
int main()
{
try {
throw std::system_error(EDOM, std::generic_category(), "hello world");
} catch (const std::system_error &ex) {
std::cout << ex.code() << '\n';
std::cout << ex.code().message() << '\n';
std::cout << ex.what() << '\n';
}
}
Possible output: