Defined in header <filesystem>
(1) (since C++17)
bool exists( const std::filesystem::path& p );
bool exists( const std::filesystem::path& p, std::error_code& ec )
(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) Equivalent to exists(status(p)) or exists(status(p, ec)) (symlinks are followed). The non-throwing overload returns false if an error occurs.


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

Return value

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


noexcept specification:  
2) 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 argument and the OS error code as the error code argument. std::bad_alloc may be thrown if memory allocation fails. 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. This overload has
noexcept specification:  


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())


#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()
    std::ofstream("sandbox/file"); // create regular file
    fs::create_symlink("non-existing", "sandbox/symlink");
    for(auto it = fs::directory_iterator("sandbox"); it != fs::directory_iterator(); ++it)
        demo_exists(*it, it->status()); // use cached status from directory entry


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

See also

determines file attributes
determines file attributes, checking the symlink target
represents file type and permissions
status of the file designated by this directory entry
symlink_status of the file designated by this directory entry
(public member function of std::filesystem::directory_entry)