Creates a hard linklink with its target set totarget as if by POSIXlink(): the pathnametarget must exist.

Once created,link andtarget are two logical names that refer to the same file (they areequivalent). Even if the original nametarget is deleted, the file continues to exist and is accessible aslink.

[edit]Parameters

[edit]Return value

(none)

[edit]Exceptions

Any overload not markednoexcept may throwstd::bad_alloc if memory allocation fails.

[edit]Notes

Some operating systems do not support hard links at all or support them only for regular files.

Some file systems do not support hard links regardless of the operating system: the FAT file system used on memory cards and flash drives, for example.

Some file systems limit the number of links per file.

Hardlinking to directories is typically restricted to the superuser.

Hard links typically cannot cross filesystem boundaries.

The special pathname dot (".") is a hard link to its parent directory. The special pathname dot-dot".." is a hard link to the directory that is the parent of its parent.

[edit]Example

#include <filesystem>#include <fstream>#include <iostream>namespace fs= std::filesystem; int main(){    fs::create_directories("sandbox/subdir");std::ofstream("sandbox/a").put('a');// create regular file    fs::create_hard_link("sandbox/a","sandbox/b");    fs::remove("sandbox/a");// read from the original file via surviving hard linkchar c=std::ifstream("sandbox/b").get();std::cout<< c<<'\n';    fs::remove_all("sandbox");}

a

[edit]See also

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