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std::filesystem::directory_entry::refresh

void refresh();
void refresh( std::error_code& ec ) noexcept;
(since C++17)

Examines the filesystem object referred to by this directory entry and stores its attributes for retrieval with status, exists, is_regular_file, and other status accessors.

If an error occurs, the value of any cached attributes is unspecified.

Parameters

ec - out-parameter for error reporting in the non-throwing overload

Return value

(none).

Exceptions

The overload that does not take a std::error_code& parameter throws filesystem::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.

Notes

Many low-level OS APIs for directory traversal retrieve file attributes along with the next directory entry. The constructors and the non-const member functions of std::filesystem::directory_iterator store these attributes, if any, in the pointed-to std::filesystem::directory_entry without calling directory_entry::refresh, which makes it possible to examine the attributes of the directory entries as they are being iterated over, without making additional system calls.

Example

See also

status of the file designated by this directory entry
symlink_status of the file designated by this directory entry
(public member function)
checks whether directory entry refers to existing file system object
(public member function)
checks whether the directory entry refers to block device
(public member function)
checks whether the directory entry refers to a character device
(public member function)
checks whether the directory entry refers to a directory
(public member function)
checks whether the directory entry refers to a named pipe
(public member function)
checks whether the directory entry refers to an other file
(public member function)
checks whether the directory entry refers to a regular file
(public member function)
checks whether the directory entry refers to a named IPC socket
(public member function)
checks whether the directory entry refers to a symbolic link
(public member function)
returns the size of the file to which the directory entry refers
(public member function)
returns the number of hard links referring to the file to which the directory entry refers
(public member function)
gets or sets the time of the last data modification of the file to which the directory entry refers
(public member function)

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