NAME¶

std::experimental::filesystem::status,std::experimental::filesystem::symlink_status - std::experimental::filesystem::status,std::experimental::filesystem::symlink_status

Synopsis¶

Defined in header <experimental/filesystem>
file_status status(const path& p); (1) (filesystem TS)
file_status status(const path& p, error_code& ec) noexcept;
file_status symlink_status(const path& p);
file_status symlink_status(const path& p, error_code& ec) (2) (filesystem TS)
noexcept;

1) Determines the type and attributes of the filesystem object identified by p as if
by POSIX stat (symlinks are followed to their targets).

* If p is a regular file, returns file_status(file_type::regular).
* If p is a directory, returns file_status(file_type::directory)
* If p is a block special file, returns file_status(file_type::block)
* If p is a character special file, returns
file_status(file_type::character)
* If p is a fifo or pipe file, returns file_status(file_type::fifo)
* If p is a socket, returns file_status(file_type::socket)
* If p does not exist, returns file_status(file_type::not_found)
* If p exists but file attributes cannot be determined, e.g. due to lack
of permissions, returns file_status(file_type::unknown)
* If errors prevent even knowing whether p exists, the non-throwing
overload sets ec and returns file_status(file_type::none), and the
throwing overload throws filesystem_error
* Otherwise, returns file_status(file_type::unknown)

2) Same as (1) except that the behavior is as if the POSIX lstat is used (symlinks
are not followed):

* If p is a symlink, returns file_status(file_type::symlink)

Parameters¶

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

Return value¶

The file status (a file_status object)

Exceptions¶

The overload that does not take a 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 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:
noexcept

Notes¶

The information provided by this function is usually also provided as a byproduct of
directory iteration, and may be obtained by the member functions of directory_entry.
During directory iteration, calling status again is unnecessary.

Example¶

// Run this code

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

namespace fs = std::experimental::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");
std::ofstream("sandbox/file"); // create regular file
fs::create_directory("sandbox/dir");
mkfifo("sandbox/pipe", 0644);
struct 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, (struct 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

See also¶

file_status represents file type and permissions
(class)
status_known checks whether file status is known
(function)
is_block_file checks whether the given path refers to block device
(function)
is_character_file checks whether the given path refers to a character device
(function)
is_directory checks whether the given path refers to a directory
(function)
is_fifo checks whether the given path refers to a named pipe
(function)
is_other checks whether the argument refers to an other file
(function)
is_regular_file checks whether the argument refers to a regular file
(function)
is_socket checks whether the argument refers to a named IPC socket
(function)
is_symlink checks whether the argument refers to a symbolic link
(function)
exists checks whether path refers to existing file system object
(function)
cached status of the file designated by this directory entry
status cached symlink_status of the file designated by this directory
symlink_status entry
(public member function of
std::experimental::filesystem::directory_entry)