W3cubDocs

/C++

std::filesystem::is_empty

Defined in header <filesystem>
bool is_empty( const std::filesystem::path& p );
bool is_empty( const std::filesystem::path& p, std::error_code& ec );
(since C++17)

Checks whether the given path refers to an empty file or directory.

Parameters

p - path to examine
ec - error code to modify in case of error

Return value

true if the file indicated by p or if the type indicated s refers to an empty file or directory, false otherwise. The non-throwing overload returns false if an error occurs.

Exceptions

The overload that does not take a std::error_code& parameter throws filesystem_error on underlying OS API errors, constructed with p as the first path argument and the OS error code as the error code argument. The overload taking a std::error_code& parameter sets it to the OS API error code if an OS API call fails, and executes ec.clear() if no errors occur. Any overload not marked noexcept may throw std::bad_alloc if memory allocation fails.

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 3013 C++17 error_code overload marked noexcept but can allocate memory noexcept removed

Example

See also

(C++17)(C++17)
determines file attributes
determines file attributes, checking the symlink target
(function)
(C++17)
checks whether path refers to existing file system object
(function)

© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
http://en.cppreference.com/w/cpp/filesystem/is_empty