std::filesystem::copy_options

 

C++

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Technical specifications

Symbols index

External libraries

 

Filesystem library

Classes
filesystem::path filesystem::filesystem_error filesystem::directory_entry filesystem::directory_iterator filesystem::recursive_directory_iterator      filesystem::file_status	filesystem::space_info filesystem::file_type filesystem::perms filesystem::perm_options filesystem::copy_options filesystem::directory_options filesystem::file_time_type
Functions
filesystem::absolute filesystem::canonicalfilesystem::weakly_canonical filesystem::relativefilesystem::proximate filesystem::copy filesystem::copy_file filesystem::copy_symlink filesystem::create_directory filesystem::create_directories filesystem::create_hard_link filesystem::create_symlink filesystem::create_directory_symlink filesystem::current_path	filesystem::exists filesystem::equivalent filesystem::file_size filesystem::hard_link_count filesystem::last_write_time filesystem::permissions filesystem::read_symlink filesystem::remove filesystem::remove_all filesystem::rename filesystem::resize_file filesystem::space filesystem::status filesystem::symlink_status filesystem::temp_directory_path
File types
filesystem::is_block_file filesystem::is_character_file filesystem::is_directory filesystem::is_empty filesystem::status_known	filesystem::is_fifo filesystem::is_other filesystem::is_regular_file filesystem::is_socket filesystem::is_symlink

 

Defined in header <filesystem>
enum class copy_options {     none = /* unspecified */,     skip_existing = /* unspecified */,     overwrite_existing = /* unspecified */,     update_existing = /* unspecified */,     recursive = /* unspecified */,     copy_symlinks = /* unspecified */,     skip_symlinks = /* unspecified */,     directories_only = /* unspecified */,     create_symlinks = /* unspecified */,     create_hard_links = /* unspecified */ };		(since C++17)

This type represents available options that control the behavior of the copy() and copy_file() function.

copy_options satisfies the requirements of BitmaskType (which means the bitwise operators operator&, operator|, operator^, operator~, operator&=, operator|=, and operator^= are defined for this type). none represents the empty bitmask; every other enumerator represents a distinct bitmask element.

Member constants

At most one copy option in each of the following options groups may be present, otherwise the behavior of the copy functions is undefined.

Member constant	Meaning
options controlling copy_file() when the file already exists
none	Report an error (default behavior).
skip_existing	Keep the existing file, without reporting an error.
overwrite_existing	Replace the existing file.
update_existing	Replace the existing file only if it is older than the file being copied.
options controlling the effects of copy() on subdirectories
none	Skip subdirectories (default behavior).
recursive	Recursively copy subdirectories and their content.
options controlling the effects of copy() on symbolic links
none	Follow symlinks (default behavior).
copy_symlinks	Copy symlinks as symlinks, not as the files they point to.
skip_symlinks	Ignore symlinks.
options controlling the kind of copying copy() does
none	Copy file content (default behavior).
directories_only	Copy the directory structure, but do not copy any non-directory files.
create_symlinks	Instead of creating copies of files, create symlinks pointing to the originals. Note: the source path must be an absolute path unless the destination path is in the current directory.
create_hard_links	Instead of creating copies of files, create hardlinks that resolve to the same files as the originals.

Example

Run this code

#include <cstdlib>
#include <filesystem>
#include <fstream>
#include <iostream>
namespace fs = std::filesystem;
 
int main()
{
    fs::create_directories("sandbox/dir/subdir");
    std::ofstream("sandbox/file1.txt").put('a');
    fs::copy("sandbox/file1.txt", "sandbox/file2.txt"); // copy file
    fs::copy("sandbox/dir", "sandbox/dir2"); // copy directory (non-recursive)
    const auto copyOptions = fs::copy_options::update_existing
                           | fs::copy_options::recursive
                           | fs::copy_options::directories_only
                           ;
    fs::copy("sandbox", "sandbox_copy", copyOptions); 
    static_cast<void>(std::system("tree"));
    fs::remove_all("sandbox");
    fs::remove_all("sandbox_copy");
}

Possible output:

.
├── sandbox
│   ├── dir
│   │   └── subdir
│   ├── dir2
│   ├── file1.txt
│   └── file2.txt
└── sandbox_copy
    ├── dir
    │   └── subdir
    └── dir2
 
8 directories, 2 files

See also

copy (C++17)	copies files or directories (function)
copy_file (C++17)	copies file contents (function)