std::filesystem::hard_link_count
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Filesystem library
filesystem::hard_link_count
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,
std::error_code & ec ) noexcept;
(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.
[edit] Parameters
p
-
path to examine
ec
-
out-parameter for error reporting in the non-throwing overload
[edit] Return value
The number of hard links for p.
[edit] Exceptions
Any overload not marked noexcept may throw std::bad_alloc if memory allocation 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.
[edit] 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 number // of hard links for any directory is 2 plus number of direct subdirectories p = fs::current_path() / ".."; // Each dot-dot is a hard link to parent 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
[edit] See also
returns the number of hard links referring to the file to which the directory entry refers
(public member function of
(public member function of
std::filesystem::directory_entry) [edit]