std::system_error::system_error

From cppreference.com


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, const std::string& what_arg);	(4)	(since C++11)

system_error( int ev, const std::error_category& ecat, const char* what_arg);	(4)	(since C++11)

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.

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.

[edit] Parameters

ec	-	error code
ev	-	error code in base encoding
ecat	-	the category of error
what_arg	-	explanatory string

[edit] Example

Demonstrates how to create a system_error exception from a errno value

run this code

#include <iostream>
#include <system_error>
 
int main()
{
    try
    {
        throw std::system_error(EDOM, std::system_category());
    }
    catch (const std::system_error& error)
    {
        std::cout << "Error: " << error.code()
                  << " - " << error.code().message() << '\n';
    }
}

Output:

Error: system:33 - Numerical argument out of domain

Language
Standard library headers
Concepts
Utilities library
Strings library
Containers library
Algorithms library
Iterators library
Numerics library
Input/output library
Localizations library
Regular expressions library (C++11)
Atomic operations library (C++11)
Thread support library (C++11)