cppdraft_translate/cppdraft/fs/op/copy.md

[fs.op.copy]

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]

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

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

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

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

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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);

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

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Effects: Before the first use of f and t:

• (4.1)

If(options & copy_options::create_symlinks) != copy_options::none ||(options & copy_options::skip_symlinks) != copy_options::none then auto f = symlink_status(from) and if needed auto t = symlink_status(to).

• (4.2)

Otherwise, if(options & copy_options::copy_symlinks) != copy_options::none then auto f = symlink_status(from) and if needed auto t = status(to).

• (4.3)

Otherwise, auto f = status(from) and if needed auto t = status(to).

Effects are then as follows:

• (4.4)

  If f.type() or t.type() is an implementation-defined file type ([fs.enum.file.type]), then the effects areimplementation-defined.

• (4.5)

  Otherwise, an error is reported as specified in [fs.err.report] if

  • (4.5.1)

exists(f) is false, or

• (4.5.2)

equivalent(from, to) is true, or

• (4.5.3)

is_other(f) || is_other(t) is true, or

• (4.5.4)

is_directory(f) && is_regular_file(t) is true.

• (4.6)

  Otherwise, if is_symlink(f), then:

  • (4.6.1)

    If(options & copy_options​::​skip_symlinks) != copy_options​::​none then return.

  • (4.6.2)

    Otherwise if!exists(t) && (options & copy_options::copy_symlinks) != copy_options::none then copy_symlink(from, to).

  • (4.6.3)

    Otherwise report an error as specified in [fs.err.report].

• (4.7)

  Otherwise, if is_regular_file(f), then:

  • (4.7.1)

    If (options & copy_options​::​directories_only) != copy_options​::​none, then return.

  • (4.7.2)

    Otherwise, if (options & copy_options​::​create_symlinks) != copy_options​::​none, then create a symbolic link to the source file.

  • (4.7.3)

    Otherwise, if (options & copy_options​::​create_hard_links) != copy_options​::​none, then create a hard link to the source file.

  • (4.7.4)

    Otherwise, if is_directory(t), then copy_file(from, to/from.filename(), options).

  • (4.7.5)

    Otherwise, copy_file(from, to, options).

• (4.8)

  Otherwise, ifis_directory(f) &&(options & copy_options::create_symlinks) != copy_options::none then report an error with an error_code argument equal to make_error_code(errc​::​is_a_directory).

• (4.9)

  Otherwise, ifis_directory(f) &&((options & copy_options::recursive) != copy_options::none || options == copy_options::none) then:

  • (4.9.1)

If exists(t) is false, then create_directory(to, from).

• (4.9.2)

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].

• (4.10)

  Otherwise, for the signature with argument ec, ec.clear().

• (4.11)

  Otherwise, no effects.

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Throws: As specified in [fs.err.report].

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

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[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]