NAME¶

std::filesystem::path::make_preferred - std::filesystem::path::make_preferred

Synopsis¶

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>

int main()
{
std::filesystem::path
windows_path("a\\b\\c"),
posix_path("a/b/c");

std::cout
<< "Windows path: "
<< windows_path << " -> "
<< windows_path.make_preferred() << '\n'
<< "POSIX path: "
<< posix_path << " -> "
<< posix_path.make_preferred() << '\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¶

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