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std::filesystem::file_type

From cppreference.com
 
 
 
Defined in header <filesystem>
enum class file_type {

    none = /* unspecified */,
    not_found = /* unspecified */,
    regular = /* unspecified */,
    directory = /* unspecified */,
    symlink = /* unspecified */,
    block = /* unspecified */,
    character = /* unspecified */,
    fifo = /* unspecified */,
    socket = /* unspecified */,
    unknown = /* unspecified */,
    /* implementation-defined */

};
(since C++17)

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

[edit] 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
implementation-defined an additional implementation-defined constant for each 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

[edit] Example

#include <iostream>
#include <fstream>
#include <cstdio>
#include <cstring>
#include <filesystem>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/stat.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");
    std::ofstream("sandbox/file"); // create regular file
    fs::create_directory("sandbox/dir");
    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);
    fs::create_symlink("file", "sandbox/symlink");
 
    // 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
    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

[edit] See also

represents file type and permissions
(class) [edit]
checks whether the given path refers to block device
(function) [edit]
checks whether the given path refers to a character device
(function) [edit]
checks whether the given path refers to a directory
(function) [edit]
(C++17)
checks whether the given path refers to a named pipe
(function) [edit]
(C++17)
checks whether the argument refers to an other file
(function) [edit]
(C++17)
checks whether the argument refers to a named IPC socket
(function) [edit]
checks whether the argument refers to a symbolic link
(function) [edit]
checks whether the directory entry refers to a regular file
(public member function of std::filesystem::directory_entry) [edit]