std::system_error::system_error

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std::system_error

Member functions
system_error::system_error
system_error::operator=
system_error::code
system_error::what

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system_error(std::error_code ec);	(1)	(since C++11)
system_error(std::error_code ec,conststd::string& what_arg);	(2)	(since C++11)
system_error(std::error_code ec,constchar* what_arg);	(2)	(since C++11)
system_error(int ev,conststd::error_category& ecat);	(3)	(since C++11)
system_error(int ev,conststd::error_category& ecat, conststd::string& what_arg);	(4)	(since C++11)
system_error(int ev,conststd::error_category& ecat, constchar* what_arg);	(4)	(since C++11)
system_error(const system_error& other)noexcept;	(5)	(since C++11)

Constructs new system error object.

1) Constructs with error codeec.

2) Constructs with error codeec and explanation stringwhat_arg. The string returned bywhat() is guaranteed to containwhat_arg as a substring.

3) Constructs with underlying error codeev and associated error categoryecat.

4) Constructs with underlying error codeev, associated error categoryecat and explanatory stringwhat_arg. The string returned bywhat() is guaranteed to containwhat_arg as a substring (assuming that it doesn't contain an embedded null character).

5) Copy constructor. Initializes the contents with those ofother. If*this andother both have dynamic typestd::system_error thenstd::strcmp(what(), other.what())==0.

[edit]Parameters

ec	-	error code
ev	-	underlying error code in the enumeration associated withecat
ecat	-	the category of error
what_arg	-	explanatory string
other	-	another`system_error` to copy

[edit]Example

Demonstrates how to create asystem_error exception from anerrno value.

Run this code

#include <iostream>#include <system_error> int main(){try{throwstd::system_error(EDOM,std::generic_category(),"FIX ME");}catch(conststd::system_error& ex){std::cout<<"code:    ["<< ex.code()<<"]\n""message: ["<< ex.code().message()<<"]\n""what:    ["<< ex.what()<<"]\n";}}

Possible output:

code:    [generic:33]message: [Numerical argument out of domain]what:    [FIX ME: Numerical argument out of domain]

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std::system_error::system_error

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