[fs.op.copy] (original) (raw)

31 Input/output library [input.output]

31.12 File systems [filesystems]

31.12.13 Filesystem operation functions [fs.op.funcs]

31.12.13.4 Copy [fs.op.copy]

void filesystem::copy(const path& from, const path& to);

Effects: Equivalent tocopy(from, to, copy_options​::​none).

void filesystem::copy(const path& from, const path& to, error_code& ec);

Effects: Equivalent tocopy(from, to, copy_options​::​none, ec).

void filesystem::copy(const path& from, const path& to, copy_options options);void filesystem::copy(const path& from, const path& to, copy_options options, error_code& ec);

Preconditions: At most one element from each option group ([fs.enum.copy.opts]) is set in options.

Effects: Before the first use of f and t:

• If(options & copy_options::create_symlinks) != copy_options::none || (options & copy_options::skip_symlinks) != copy_options::nonethen auto f = symlink_status(from) and if needed auto t = symlink_status(to).
• Otherwise, if(options & copy_options::copy_symlinks) != copy_options::nonethen auto f = symlink_status(from) and if needed auto t = status(to).
• Otherwise, auto f = status(from) and if needed auto t = status(to).

Effects are then as follows:

• If f.type() or t.type() is an implementation-defined file type ([fs.enum.file.type]), then the effects areimplementation-defined.
• Otherwise, an error is reported as specified in [fs.err.report] if
  • exists(f) is false, or
  • equivalent(from, to) is true, or
  • is_other(f) || is_other(t) is true, or
  • is_directory(f) && is_regular_file(t) is true.
• Otherwise, if is_symlink(f), then:
  • If(options & copy_options​::​skip_symlinks) != copy_options​::​nonethen return.
  • Otherwise if!exists(t) && (options & copy_options::copy_symlinks) != copy_options::nonethen copy_symlink(from, to).
• Otherwise, if is_regular_file(f), then:
  • If (options & copy_options​::​directories_only) != copy_options​::​none, then return.
  • Otherwise, if (options & copy_options​::​create_symlinks) != copy_options​::​none, then create a symbolic link to the source file.
  • Otherwise, if (options & copy_options​::​create_hard_links) != copy_options​::​none, then create a hard link to the source file.
  • Otherwise, if is_directory(t), then copy_file(from, to/from.filename(), options).
  • Otherwise, copy_file(from, to, options).
• Otherwise, ifis_directory(f) && (options & copy_options::create_symlinks) != copy_options::nonethen report an error with an error_code argument equal to make_error_code(errc​::​is_a_directory).
• Otherwise, ifis_directory(f) && ((options & copy_options::recursive) != copy_options::none || options == copy_options::none) then:
  • If exists(t) is false, then create_directory(to, from).
  • Then, iterate over the files in from, as if byfor (const directory_entry& x : directory_iterator(from)) copy(x.path(), to/x.path().filename(), options | copy_options::in-recursive-copy); where in-recursive-copy is a bitmask element of copy_options that is not one of the elements in [fs.enum.copy.opts].
• Otherwise, for the signature with argument ec, ec.clear().

Remarks: For the signature with argument ec, any library functions called by the implementation shall have an error_code argument if applicable.

[Example 1:

Given this directory structure:

/dir1 file1 file2 dir2 file3

Calling copy("/dir1", "/dir3") would result in:

/dir1 file1 file2 dir2 file3 /dir3 file1 file2

Alternatively, calling copy("/dir1", "/dir3", copy_options​::​recursive) would result in:

/dir1 file1 file2 dir2 file3 /dir3 file1 file2 dir2 file3

— _end example_]