NAME¶

std::experimental::filesystem::directory_entry::status, - std::experimental::filesystem::directory_entry::status,

Synopsis¶

file_status status() const; (1) (filesystem TS)
file_status status( error_code& ec ) const;
file_status symlink_status() const; (2) (filesystem TS)
file_status symlink_status( error_code& ec ) const;

1) Returns the potentially cached status of the entry, as if determined by a status
call (symlinks are followed to their targets)
2) Returns the potentially cached status of the entry, as if determined by a
symlink_status call (symlinks are not followed)

Parameters¶

ec - out-parameter for error reporting in the non-throwing overload

Return value¶

The status of the file referred to by the entry.

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 file status information is usually provided as a byproduct of directory
iteration, in which case it is cached and may be obtained by these member functions
without the cost of an additional system call. During directory iteration, calling
status is unnecessary and accessors such as is_directory should be called with the
cached status value, not with a path.

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 determines file attributes
symlink_status determines file attributes, checking the symlink target
(function)
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)