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Showing content from https://en.cppreference.com/w/cpp/language/../../cpp/../cpp/filesystem/directory_entry/status.html below:

std::filesystem::directory_entry::status, std::filesystem::directory_entry::symlink_status - cppreference.com

1,2)

Returns status of the entry, as if determined by a

filesystem::status

call (symlinks are followed to their targets).

[edit] Parameters ec - out-parameter for error reporting in the non-throwing overload [edit] Return value

The status of the file referred to by the entry.

[edit] Exceptions

Any overload not marked noexcept may throw std::bad_alloc if memory allocation fails.

1,3)

Throws

std::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.

2,4)

Sets a

std::error_code&

parameter to the OS API error code if an OS API call fails, and executes

ec.clear()

if no errors occur.

[edit] Notes

Many low-level OS APIs for directory traversal retrieve file attributes along with the next directory entry. The constructors and the non-const member functions of std::filesystem::directory_iterator store these attributes, if any, in the pointed-to std::filesystem::directory_entry without calling directory_entry::refresh, which makes it possible to examine the attributes of the directory entries as they are being iterated over, without making additional system calls.

[edit] Example
#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;
    // alternative: switch(s.type()) { case fs::file_type::regular: ...}
    if (fs::is_regular_file(s))
        std::cout << " is a regular file\n";
    if (fs::is_directory(s))
        std::cout << " is a directory\n";
    if (fs::is_block_file(s))
        std::cout << " is a block device\n";
    if (fs::is_character_file(s))
        std::cout << " is a character device\n";
    if (fs::is_fifo(s))
        std::cout << " is a named IPC pipe\n";
    if (fs::is_socket(s))
        std::cout << " is a named IPC socket\n";
    if (fs::is_symlink(s))
        std::cout << " is a symlink\n";
    if (!fs::exists(s))
        std::cout << " does not exist\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
[edit] See also updates the cached file attributes
(public member function) [edit] checks whether directory entry refers to existing file system object
(public member function) [edit] checks whether the directory entry refers to block device
(public member function) [edit] checks whether the directory entry refers to a character device
(public member function) [edit] checks whether the directory entry refers to a directory
(public member function) [edit] checks whether the directory entry refers to a named pipe
(public member function) [edit] checks whether the directory entry refers to an other file
(public member function) [edit] checks whether the directory entry refers to a regular file
(public member function) [edit] checks whether the directory entry refers to a named IPC socket
(public member function) [edit] checks whether the directory entry refers to a symbolic link
(public member function) [edit] returns the size of the file to which the directory entry refers
(public member function) [edit] returns the number of hard links referring to the file to which the directory entry refers
(public member function) [edit] gets the time of the last data modification of the file to which the directory entry refers
(public member function) [edit]

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