Defined in header <filesystem> | ||
enumclass file_type{ none=/* unspecified */, | (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.
| Enumerator | 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 |
unknown | the file exists but its type could not be determined |
| implementation-defined | an additional implementation-defined constant for each additional file type supported by the implementation (e.g., MSVC STL definesjunction forNTFS junctions) |
#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 accessorsfor(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
(C++17) | represents file type and permissions (class)[edit] |
(C++17) | checks whether the given path refers to block device (function)[edit] |
(C++17) | checks whether the given path refers to a character device (function)[edit] |
(C++17) | 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 another file (function)[edit] |
(C++17) | checks whether the argument refers to a named IPC socket (function)[edit] |
(C++17) | 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] |
