clone.h

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#ifndef __DEDUP_CLONE_H__
#define __DEDUP_CLONE_H__

/// replace_with_clone
///
/// The `replace_with_clone` function causes the link named `dst` to be
/// replaced with a clone of `src`. Unlike `clonefile(2)`, it is expected
/// that `dst` already exists. All metadata (mode, flags, & ACLs)
/// are retained on `dst`. The current user must have read access to both
/// `src` and `dst` and write access to `dst` and the directory where
/// `dst` resides.
///
/// `src` and `dst` must be on the same volume. (TODO: is it enough
/// that they are with in the same APFS partition, can clones span
/// volume boundaries?).
///
/// On success `dst` will have its data replaced with copy-on-write,
/// cloned blocks from `src` and `replace_with_clone` returns 0.
///
/// On failure clonefile will return one of the following values:
///
///   [ENOMEM]     the name of the temporary file is longer than `PATH_MAX`
///
///   In addition, `replace_with_clone` may return any error
///   returned by `clonefile(2)`, `copyfile(2)`, or `rename(2)`.
///
/// See also: `clonefile(2)`, `copyfile(2)`, or `rename(2)`
int replace_with_clone(const char* src, const char* dst);

int replace_with_link(const char* src, const char* dst);
int replace_with_symlink(const char* src, const char* dst);

#endif // __DEDUP_CLONE_H__