home | help 
std::filesy..._link_count(3)   C++ Standard Libary  std::filesy..._link_count(3)

NAME
     std::filesystem::hard_link_count - std::filesystem::hard_link_count

Synopsis
	Defined in header <filesystem>
	std::uintmax_t	hard_link_count(  const  std::filesystem::path& p ); (1)
     (since C++17)
	std::uintmax_t hard_link_count( const  std::filesystem::path&  p,    (2)
     (since C++17)
					std::error_code& ec ) noexcept;

	Returns the number of hard links for the filesystem object identified by
     path p.

	The non-throwing overload returns static_cast<uintmax_t>(-1) on errors.

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

Return value
	The number of hard links for p.

Exceptions
	Any  overload not marked noexcept may throw std::bad_alloc if memory al-
     location
	fails.

	1) 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)  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.

Example
     // Run this code

      #include <filesystem>
      #include <iostream>
      namespace fs = std::filesystem;

      int main()
      {
	  // On a POSIX-style filesystem, each directory has  at  least  2  hard
     links:
	  // itself and the special member pathname "."
	  fs::path p = fs::current_path();
	  std::cout << "Number of hard links for current path is "
		    << fs::hard_link_count(p) << '\n';

	  // Each ".." is a hard link to the parent directory, so the total num-
     ber
	  //  of  hard links for any directory is 2 plus number of direct subdi-
     rectories
	  p = fs::current_path() / ".."; // Each dot-dot is a hard link to  par-
     ent
	  std::cout << "Number of hard links for .. is "
		    << fs::hard_link_count(p) << '\n';
      }

Possible output:
      Number of hard links for current path is 2
      Number of hard links for .. is 3

See also
	create_hard_link creates a hard link
	(C++17) 	 (function)
			 returns  the number of hard links referring to the file
     to which the
	hard_link_count  directory entry refers
			 (public  member  function  of	 std::filesystem::direc-
     tory_entry)

http://cppreference.com 	   2024.06.10	    std::filesy..._link_count(3)
home | help