bool exists() const;
bool exists( std::error_code& ec ) const noexcept;
(since C++17)

Checks whether the pointed-to object exists. Effectively returns std::filesystem::exists(status()) or std::filesystem::exists(status(ec)), respectively


[edit] Parameters

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

[edit] Return value

true if the referred-to filesystem object exists.

[edit] 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.

[edit] Example

#include <filesystem>
#include <fstream>
#include <iostream>
#include <string>
namespace fs = std::filesystem;
int main()
    // store current path to restore it at exit
    const auto old_current_path = fs::current_path();
    // create "sanbox" directory in temp dir
    const auto dir_sandbox = fs::temp_directory_path() / "sandbox";
    if (!fs::create_directory(dir_sandbox)) {
        std::cout << "ERROR #1" << '\n';
        return -1;
    fs::current_path(dir_sandbox); // switch to newly created dir
    fs::directory_entry entry_sandbox { dir_sandbox };
    if (!entry_sandbox.exists()) {
        std::cout << "ERROR #2" << '\n';
        return -1;
    std::cout << "Current dir: " << entry_sandbox.path().filename() << '\n';
    fs::path path_tmp_file = dir_sandbox / "tmp_file";
    std::ofstream file( path_tmp_file.string() ); // create regular file
    file << ""; // write 16 bytes
    fs::directory_entry entry_tmp_file{ path_tmp_file };
    if (entry_tmp_file.exists()) {
        std::cout << "File " << entry_tmp_file.path().filename()
                  << " has size: " << entry_tmp_file.file_size() << '\n';
    } else {
        std::cout << "ERROR #3" << '\n';
    // cleanup

Possible output:

Current dir: "sandbox"
File "tmp_file" has size: 16

[edit] See also

checks whether path refers to existing file system object
(function) [edit]