std::filesystem::relative, std::filesystem::proximate

Defined in header <filesystem> 
path relative( const std::filesystem::path& p,
               std::error_code& ec);
 (1) (since C++17) 
path relative( const std::filesystem::path& p,
               const std::filesystem::path& base = std::filesystem::current_path());
path relative( const std::filesystem::path& p,
               const std::filesystem::path& base,
               std::error_code& ec);
 (2) (since C++17) 
path proximate( const std::filesystem::path& p,
                std::error_code& ec);
 (3) (since C++17) 
path proximate( const std::filesystem::path& p,
                const std::filesystem::path& base = std::filesystem::current_path());
path proximate( const std::filesystem::path& p,
                const std::filesystem::path& base,
                std::error_code& ec);
 (4) (since C++17)
1) Returns relative(p, current_path(), ec)
2) Returns p made relative to base. Resolves symlinks and normalizes both p and base before other processing. Effectively returns weakly_canonical(p).lexically_relative(weakly_canonical(base)) or weakly_canonical(p, ec).lexically_relative(weakly_canonical(base, ec)), except the error code form returns path() at the first error occurrence, if any.
3) Returns proximate(p, current_path(), ec)
4) Effectively returns weakly_canonical(p).lexically_proximate(weakly_canonical(base)) or weakly_canonical(p, ec).lexically_proximate(weakly_canonical(base, ec)), except the error code form returns path() at the first error occurrence, if any.

Parameters

p - an existing path
base - base path, against which p will be made relative/proximate
ec - error code to store error status to

Return value

1) p made relative against base.
2) p made proximate against base

Exceptions

The overload that does not take a std::error_code& parameter throws filesystem_error on underlying OS API errors, constructed with p as the first path argument, base as the second path argument, and the OS error code as the error code argument. The overload taking a std::error_code& parameter sets it to the OS API error code if an OS API call fails, and executes ec.clear() if no errors occur. Any overload not marked noexcept may throw std::bad_alloc if memory allocation fails.

Example

See also

(C++17)
 represents a path
(class)
(C++17)
 composes an absolute path
(function)
(C++17)
 composes a canonical path
(function)

© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
http://en.cppreference.com/w/cpp/filesystem/relative