NAME¶

std::filesystem::file_type - std::filesystem::file_type

Synopsis¶

Defined in header <filesystem>
enum class file_type {

none = /* unspecified */,
not_found = /* unspecified */,
regular = /* unspecified */,
directory = /* unspecified */,
symlink = /* unspecified */,
block = /* unspecified */, (since C++17)
character = /* unspecified */,
fifo = /* unspecified */,
socket = /* unspecified */,
unknown = /* unspecified */,
/* implementation-defined */

};

file_type defines constants that indicate a type of a file or directory a path
refers to. The value of the enumerators are distinct.

Constants¶

Constant Meaning
none indicates that the file status has not been evaluated yet, or
an error occurred when evaluating it
not_found indicates that the file was not found (this is not considered
an error)
regular a regular file
directory a directory
symlink a symbolic link
block a block special file
character a character special file
fifo a FIFO (also known as pipe) file
socket a socket file
an additional implementation-defined constant for each
implementation-defined additional file type supported by the implementation (e.g.
MSVC STL defines junction for NTFS junctions)
unknown the file exists but its type could not be determined

Example¶

// Run this code

#include <cstdio>
#include <cstring>
#include <filesystem>
#include <fstream>
#include <iostream>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/un.h>
#include <unistd.h>

namespace fs = std::filesystem;

void demo_status(const fs::path& p, fs::file_status s)
{
std::cout << p;
switch (s.type())
{
case fs::file_type::none:
std::cout << " has `not-evaluated-yet` type";
break;
case fs::file_type::not_found:
std::cout << " does not exist";
break;
case fs::file_type::regular:
std::cout << " is a regular file";
break;
case fs::file_type::directory:
std::cout << " is a directory";
break;
case fs::file_type::symlink:
std::cout << " is a symlink";
break;
case fs::file_type::block:
std::cout << " is a block device";
break;
case fs::file_type::character:
std::cout << " is a character device";
break;
case fs::file_type::fifo:
std::cout << " is a named IPC pipe";
break;
case fs::file_type::socket:
std::cout << " is a named IPC socket";
break;
case fs::file_type::unknown:
std::cout << " has `unknown` type";
break;
default:
std::cout << " has `implementation-defined` type";
break;
}
std::cout << '\n';
}

int main()
{
// create files of different kinds
fs::create_directory("sandbox");
fs::create_directory("sandbox/dir");
std::ofstream{"sandbox/file"}; // create regular file
fs::create_symlink("file", "sandbox/symlink");

mkfifo("sandbox/pipe", 0644);
sockaddr_un addr;
addr.sun_family = AF_UNIX;
std::strcpy(addr.sun_path, "sandbox/sock");
int fd = socket(PF_UNIX, SOCK_STREAM, 0);
bind(fd, reinterpret_cast<sockaddr*>(&addr), sizeof addr);

// demo different status accessors
for (auto it{fs::directory_iterator("sandbox")}; it != fs::directory_iterator(); ++it)
demo_status(*it, it->symlink_status()); // use cached status from directory entry
demo_status("/dev/null", fs::status("/dev/null")); // direct calls to status
demo_status("/dev/sda", fs::status("/dev/sda"));
demo_status("sandbox/no", fs::status("/sandbox/no"));

// cleanup (prefer std::unique_ptr-based custom deleters)
close(fd);
fs::remove_all("sandbox");
}

Possible output:¶

"sandbox/file" is a regular file
"sandbox/dir" is a directory
"sandbox/pipe" is a named IPC pipe
"sandbox/sock" is a named IPC socket
"sandbox/symlink" is a symlink
"/dev/null" is a character device
"/dev/sda" is a block device
"sandbox/no" does not exist

See also¶

file_status represents file type and permissions
(C++17) (class)
is_block_file checks whether the given path refers to block device
(C++17) (function)
is_character_file checks whether the given path refers to a character device
(C++17) (function)
is_directory checks whether the given path refers to a directory
(C++17) (function)
is_fifo checks whether the given path refers to a named pipe
(C++17) (function)
is_other checks whether the argument refers to an other file
(C++17) (function)
is_socket checks whether the argument refers to a named IPC socket
(C++17) (function)
is_symlink checks whether the argument refers to a symbolic link
(C++17) (function)
checks whether the directory entry refers to a regular file
is_regular_file (public member function of std::filesystem::directory_entry)