Defined in header <filesystem>
bool exists( std::filesystem::file_status s ) noexcept;
(1) (since C++17)
bool exists( const std::filesystem::path& p );
bool exists( const std::filesystem::path& p, std::error_code& ec ) noexcept;
(2) (since C++17)

Checks if the given file status or path corresponds to an existing file or directory.

1) Equivalent to status_known(s) && s.type() != file_type::not_found.
2) Let s be a std::filesystem::file_status determined as if by status(p) or status(p, ec) (symlinks are followed), respectively. Returns exists(s). The non-throwing overload calls ec.clear() if status_known(s).


[edit] Parameters

s - file status to check
p - path to examine
ec - out-parameter for error reporting in the non-throwing overload

[edit] Return value

true if the given path or file status corresponds to an existing file or directory, false otherwise.

[edit] Exceptions

2) 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.

No filesystem exception is thrown if object does not exist (use return value).

[edit] Notes

The information provided by this function is usually also provided as a byproduct of directory iteration. During directory iteration, calling exists(*iterator) is less efficient than exists(iterator->status()).

[edit] Example

#include <iostream>
#include <fstream>
#include <cstdint>
#include <filesystem>
namespace fs = std::filesystem;
void demo_exists(const fs::path& p, fs::file_status s = fs::file_status{})
    std::cout << p;
    if(fs::status_known(s) ? fs::exists(s) : fs::exists(p))
        std::cout << " exists\n";
        std::cout << " does not exist\n";
int main()
    const fs::path sandbox{"sandbox"};
    std::ofstream{sandbox/"file"}; // create regular file
    fs::create_symlink("non-existing", sandbox/"symlink");
    for (const auto& entry : fs::directory_iterator(sandbox))
        demo_exists(entry, entry.status()); // use cached status from directory entry


"sandbox" exists
"sandbox/symlink" does not exist
"sandbox/file" exists

[edit] See also

determines file attributes
determines file attributes, checking the symlink target
(function) [edit]
represents file type and permissions
(class) [edit]
checks whether directory entry refers to existing file system object
(public member function of std::filesystem::directory_entry) [edit]