PathRelativePathToA

// SHLWAPI.dll  (ANSI / -A)
#include <windows.h>

BOOL PathRelativePathToA(
    LPSTR pszPath,
    LPCSTR pszFrom,
    DWORD dwAttrFrom,
    LPCSTR pszTo,
    DWORD dwAttrTo
);

<DllImport("SHLWAPI.dll", CharSet:=CharSet.Ansi, ExactSpelling:=True)>
Public Shared Function PathRelativePathToA(
    <MarshalAs(UnmanagedType.LPStr)> pszPath As System.Text.StringBuilder,   ' LPSTR out
    <MarshalAs(UnmanagedType.LPStr)> pszFrom As String,   ' LPCSTR
    dwAttrFrom As UInteger,   ' DWORD
    <MarshalAs(UnmanagedType.LPStr)> pszTo As String,   ' LPCSTR
    dwAttrTo As UInteger   ' DWORD
) As Boolean
End Function

' pszPath : LPSTR out
' pszFrom : LPCSTR
' dwAttrFrom : DWORD
' pszTo : LPCSTR
' dwAttrTo : DWORD
Declare PtrSafe Function PathRelativePathToA Lib "shlwapi" ( _
    ByVal pszPath As String, _
    ByVal pszFrom As String, _
    ByVal dwAttrFrom As Long, _
    ByVal pszTo As String, _
    ByVal dwAttrTo As Long) As Long
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

PathRelativePathToA = ctypes.windll.shlwapi.PathRelativePathToA
PathRelativePathToA.restype = wintypes.BOOL
PathRelativePathToA.argtypes = [
    wintypes.LPSTR,  # pszPath : LPSTR out
    wintypes.LPCSTR,  # pszFrom : LPCSTR
    wintypes.DWORD,  # dwAttrFrom : DWORD
    wintypes.LPCSTR,  # pszTo : LPCSTR
    wintypes.DWORD,  # dwAttrTo : DWORD
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('SHLWAPI.dll')
PathRelativePathToA = Fiddle::Function.new(
  lib['PathRelativePathToA'],
  [
    Fiddle::TYPE_VOIDP,  # pszPath : LPSTR out
    Fiddle::TYPE_VOIDP,  # pszFrom : LPCSTR
    -Fiddle::TYPE_INT,  # dwAttrFrom : DWORD
    Fiddle::TYPE_VOIDP,  # pszTo : LPCSTR
    -Fiddle::TYPE_INT,  # dwAttrTo : DWORD
  ],
  Fiddle::TYPE_INT)

#[link(name = "shlwapi")]
extern "system" {
    fn PathRelativePathToA(
        pszPath: *mut u8,  // LPSTR out
        pszFrom: *const u8,  // LPCSTR
        dwAttrFrom: u32,  // DWORD
        pszTo: *const u8,  // LPCSTR
        dwAttrTo: u32  // DWORD
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[return: MarshalAs(UnmanagedType.Bool)]
[DllImport("SHLWAPI.dll", CharSet = CharSet.Ansi)]
public static extern bool PathRelativePathToA([MarshalAs(UnmanagedType.LPStr)] System.Text.StringBuilder pszPath, [MarshalAs(UnmanagedType.LPStr)] string pszFrom, uint dwAttrFrom, [MarshalAs(UnmanagedType.LPStr)] string pszTo, uint dwAttrTo);
"@
$api = Add-Type -MemberDefinition $sig -Name 'SHLWAPI_PathRelativePathToA' -Namespace Win32 -PassThru
# $api::PathRelativePathToA(pszPath, pszFrom, dwAttrFrom, pszTo, dwAttrTo)

#uselib "SHLWAPI.dll"
#func global PathRelativePathToA "PathRelativePathToA" sptr, sptr, sptr, sptr, sptr
; PathRelativePathToA varptr(pszPath), pszFrom, dwAttrFrom, pszTo, dwAttrTo   ; 戻り値は stat
; pszPath : LPSTR out -> "sptr"
; pszFrom : LPCSTR -> "sptr"
; dwAttrFrom : DWORD -> "sptr"
; pszTo : LPCSTR -> "sptr"
; dwAttrTo : DWORD -> "sptr"
; ※HSP3.7は #func のため戻り値はシステム変数 stat に格納されます。

#uselib "SHLWAPI.dll"
#cfunc global PathRelativePathToA "PathRelativePathToA" var, str, int, str, int
; res = PathRelativePathToA(pszPath, pszFrom, dwAttrFrom, pszTo, dwAttrTo)
; pszPath : LPSTR out -> "var"
; pszFrom : LPCSTR -> "str"
; dwAttrFrom : DWORD -> "int"
; pszTo : LPCSTR -> "str"
; dwAttrTo : DWORD -> "int"
; ※出力/バッファ引数は var 方式(変数を直接渡す)。varptr 方式にも切替可。

; BOOL PathRelativePathToA(LPSTR pszPath, LPCSTR pszFrom, DWORD dwAttrFrom, LPCSTR pszTo, DWORD dwAttrTo)
#uselib "SHLWAPI.dll"
#cfunc global PathRelativePathToA "PathRelativePathToA" var, str, int, str, int
; res = PathRelativePathToA(pszPath, pszFrom, dwAttrFrom, pszTo, dwAttrTo)
; pszPath : LPSTR out -> "var"
; pszFrom : LPCSTR -> "str"
; dwAttrFrom : DWORD -> "int"
; pszTo : LPCSTR -> "str"
; dwAttrTo : DWORD -> "int"
; ※出力/バッファ引数は var 方式(変数を直接渡す)。varptr 方式にも切替可。

import (
	"golang.org/x/sys/windows"
	"unsafe"
)

var (
	shlwapi = windows.NewLazySystemDLL("SHLWAPI.dll")
	procPathRelativePathToA = shlwapi.NewProc("PathRelativePathToA")
)

// pszPath (LPSTR out), pszFrom (LPCSTR), dwAttrFrom (DWORD), pszTo (LPCSTR), dwAttrTo (DWORD)
r1, _, err := procPathRelativePathToA.Call(
	uintptr(pszPath),
	uintptr(unsafe.Pointer(windows.BytePtrFromString(pszFrom))),
	uintptr(dwAttrFrom),
	uintptr(unsafe.Pointer(windows.BytePtrFromString(pszTo))),
	uintptr(dwAttrTo),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // BOOL

function PathRelativePathToA(
  pszPath: PAnsiChar;   // LPSTR out
  pszFrom: PAnsiChar;   // LPCSTR
  dwAttrFrom: DWORD;   // DWORD
  pszTo: PAnsiChar;   // LPCSTR
  dwAttrTo: DWORD   // DWORD
): BOOL; stdcall;
  external 'SHLWAPI.dll' name 'PathRelativePathToA';

result := DllCall("SHLWAPI\PathRelativePathToA"
    , "Ptr", pszPath   ; LPSTR out
    , "AStr", pszFrom   ; LPCSTR
    , "UInt", dwAttrFrom   ; DWORD
    , "AStr", pszTo   ; LPCSTR
    , "UInt", dwAttrTo   ; DWORD
    , "Int")   ; return: BOOL

●PathRelativePathToA(pszPath, pszFrom, dwAttrFrom, pszTo, dwAttrTo) = DLL("SHLWAPI.dll", "bool PathRelativePathToA(char*, char*, dword, char*, dword)")
# 呼び出し: PathRelativePathToA(pszPath, pszFrom, dwAttrFrom, pszTo, dwAttrTo)
# pszPath : LPSTR out -> "char*"
# pszFrom : LPCSTR -> "char*"
# dwAttrFrom : DWORD -> "dword"
# pszTo : LPCSTR -> "char*"
# dwAttrTo : DWORD -> "dword"
# なでしこ1は32bit・ANSI(Shift_JIS)。文字列=char*(ANSI)、ポインタ/ハンドル=void*(4byte)。