bool filesystem::copy_file(const path& from, const path& to); bool filesystem::copy_file(const path& from, const path& to, error_code& ec);

Returns: copy_file(from, to, copy_options​::​none) or

copy_file(from, to, copy_options​::​none, ec), respectively.

bool filesystem::copy_file(const path& from, const path& to, copy_options options); bool filesystem::copy_file(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: As follows:

• Report an error as specified in [fs.err.report] if

  • is_regular_file(from) is false, or
  • exists(to) is true and is_regular_file(to) is false, or
  • exists(to) is true and equivalent(from, to) is true, or
  • exists(to) is true and (options & (copy_options::skip_existing | copy_options::overwrite_existing | copy_options::update_existing)) == copy_options::none

• Otherwise, copy the contents and attributes of the file from resolves to, to the file to resolves to, if

  • exists(to) is false, or
  • (options & copy_options​::​overwrite_existing) != copy_options​::​none, or
  • (options & copy_options​::​update_existing) != copy_options​::​none and from is more recent than to, determined as if by use of the last_write_time function ([fs.op.last.write.time]).

Returns: true if the from file was copied, otherwise false.

The signature with argument ec returns false if an error occurs.

Complexity: At most one direct or indirect invocation of status(to).