std::filesystem::path::make_preferred

 

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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

 

std::filesystem::path

Constants
path::native_formatpath::generic_formatpath::auto_format
Member functions
path::path path::~path path::operator= path::assign path::appendpath::operator /= path::concatpath::operator += path::clear path::make_preferred path::remove_filename path::replace_filename path::replace_extension      path::swap path::compare path::beginpath::end	path::c_strpath::nativepath::operator string_type path::stringpath::u8stringpath::u16stringpath::u32stringpath::wstring path::generic_stringpath::generic_u8stringpath::generic_u16stringpath::generic_u32stringpath::generic_wstring path::lexically_normalpath::lexically_relativepath::lexically_proximate
Path decomposition
path::root_name path::root_directory path::root_path path::relative_path path::parent_path path::filename path::stem path::extension path::empty	path::has_root_pathpath::has_root_namepath::has_root_directorypath::has_relative_pathpath::has_parent_pathpath::has_filenamepath::has_stempath::has_extension path::is_absolutepath::is_relative
Non-member functions
operator==operator!=operator<operator<=operator>operator>=operator<=> (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20)	operator/ operator<<operator>> swap(path) hash_value u8path
Helper Classes
hash

 

path& make_preferred();		(since C++17)

Converts all directory separators in the generic-format view of the path to the preferred directory separator.

For example, on Windows, where \ is the preferred separator, the path foo/bar will be converted to foo\bar.

Parameters

(none)

Return value

*this

Exceptions

May throw implementation-defined exceptions.

Example

Windows can use / as a separator, but prefers \, so make_preferred converts the forward slashes to backslashes. On the other hand, POSIX does not use \ as a separator, because backslashes are valid filename characters — the Windows path on POSIX actually refers to a file with the name "a\\b\\c". For this reason the "separators" are not converted.

Run this code

#include <filesystem>
#include <iostream>
#include <iomanip>
 
int main()
{
  std::filesystem::path windows_path{"a\\b\\c"};
  std::filesystem::path posix_path{"a/b/c"};
  std::cout << "Windows path: " 
            << std::quoted(windows_path.string()) << " -> " 
            << std::quoted(windows_path.make_preferred().string()) << '\n'
            << "POSIX path: "
            << std::quoted(posix_path.string()) << " -> " 
            << std::quoted(posix_path.make_preferred().string()) << '\n';
}

Output:

# on Windows
Windows path: "a\\b\\c" -> "a\\b\\c"
POSIX path: "a/b/c" -> "a\\b\\c"
# on POSIX
Windows path: "a\\b\\c" -> "a\\b\\c"
POSIX path: "a/b/c" -> "a/b/c"

See also

constexpr value_type preferred_separator [static]

alternative directory separator which may be used in addition to the portable /. On Windows, this is the backslash character \. On POSIX, this is the same forward slash / as the portable separator (public static member constant)