std::filesystem::is_socket - cppreference.com std::filesystem::is_socket From cppreference.com < cpp | filesystem C++ Language Standard library headers Concepts Utilities library Strings library Containers library Algorithms library Iterators library Numerics library Input/output library Localizations library Regular expressions library (C++11) Atomic operations library (C++11) Thread support library (C++11) Filesystem library (C++17) Technical Specifications Filesystem library Classes filesystem::path filesystem::filesystem_error filesystem::directory_entry filesystem::directory_iterator filesystem::recursive_directory_iterator filesystem::file_status filesystem::space_info filesystem::file_type filesystem::perms filesystem::copy_options filesystem::directory_options filesystem::file_time_type Functions filesystem::absolute filesystem::system_complete filesystem::canonicalfilesystem::weakly_canonical filesystem::relativefilesystem::proximate filesystem::copy filesystem::copy_file filesystem::copy_symlink filesystem::create_directory filesystem::create_directories filesystem::create_hard_link filesystem::create_symlink filesystem::create_directory_symlink filesystem::current_path filesystem::exists filesystem::equivalent filesystem::file_size filesystem::hard_link_count filesystem::last_write_time filesystem::permissions filesystem::read_symlink filesystem::remove filesystem::remove_all filesystem::rename filesystem::resize_file filesystem::space filesystem::status filesystem::symlink_status filesystem::temp_directory_path File types filesystem::is_block_file filesystem::is_character_file filesystem::is_directory filesystem::is_empty filesystem::status_known filesystem::is_fifo filesystem::is_other filesystem::is_regular_file filesystem::is_socket filesystem::is_symlink Defined in header bool is_socket( std::filesystem::file_status s ); (1) (since C++17) bool is_socket( const std::filesystem::path& p ); bool is_socket( const std::filesystem::path& p, std::error_code& ec ); (2) (since C++17) Checks if the given file status or path corresponds to a named IPC socket, as if determined by the POSIX S_IFSOCK. 1) Equivalent to s.type() == file_type::socket. 2) Equivalent to is_socket(status(p)) or is_socket(status(p, ec)). Parameters s - file status to check p - path to examine ec - out-parameter for error reporting in the non-throwing overload Return value true if the file indicated by p or if the type indicated s refers to a named socket. The non-throwing overload returns false if an error occurs. Exceptions 1) noexcept specification: noexcept 2,3) The overload that does not take a std::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 std::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 Named sockets are UNIX domain sockets constructed with socket and bind POSIX APIs, which may be used for advanced interprocess communication. In particular, they may be used to transport open file descriptors from one running process to another. Example Run this code #include
#include
#include
#include
#include
#include
#include
#include
#include
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");
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 statussymlink_status (C++17)(C++17) determines file attributes determines file attributes, checking the symlink target (function) file_status (C++17) represents file type and permissions (class) status_known (C++17) checks whether file status is known (function) is_block_file (C++17) checks whether the given path refers to block device (function) is_character_file (C++17) checks whether the given path refers to a character device (function) is_directory (C++17) checks whether the given path refers to a directory (function) is_fifo (C++17) checks whether the given path refers to a named pipe (function) is_other (C++17) checks whether the argument refers to an other file (function) is_regular_file (C++17) checks whether the argument refers to a regular file (function) is_symlink (C++17) checks whether the argument refers to a symbolic link (function) exists (C++17) checks whether path refers to existing file system object (function) statussymlink_status status of the file designated by this directory entry symlink_status of the file designated by this directory entry (public member function of std::filesystem::directory_entry) Retrieved from "http://en.cppreference.com/mwiki/index.php?title=cpp/filesystem/is_socket&oldid=91663" Category: unconditionally noexcept Hidden categories: Pages with unreviewed unconditional noexcept template Pages with unreviewed noexcept template
