3 files changed, 22 insertions, 16 deletions
diff --git a/lib/std/Io/Threaded.zig b/lib/std/Io/Threaded.zig
index fbbd9a985c..a567878b82 100644
--- a/lib/std/Io/Threaded.zig
+++ b/lib/std/Io/Threaded.zig
@@ -211,7 +211,6 @@ pub fn io(t: *Threaded) Io {
                 else => dirOpenFilePosix,
             },
             .dirOpenDir = switch (builtin.os.tag) {
-                .windows => dirOpenDirWindows,
                 .wasi => dirOpenDirWasi,
                 .haiku => dirOpenDirHaiku,
                 else => dirOpenDirPosix,
@@ -2035,6 +2034,11 @@ fn dirOpenDirPosix(
 ) Io.Dir.OpenError!Io.Dir {
     const t: *Threaded = @ptrCast(@alignCast(userdata));
 
+    if (is_windows) {
+        const sub_path_w = try windows.sliceToPrefixedFileW(dir.handle, sub_path);
+        return dirOpenDirWindows(t, dir, sub_path_w.span(), options);
+    }
+
     var path_buffer: [posix.PATH_MAX]u8 = undefined;
     const sub_path_posix = try pathToPosix(sub_path, &path_buffer);
 
@@ -2123,19 +2127,13 @@ fn dirOpenDirHaiku(
     }
 }
 
-fn dirOpenDirWindows(
-    userdata: ?*anyopaque,
+pub fn dirOpenDirWindows(
+    t: *Io.Threaded,
     dir: Io.Dir,
-    sub_path: []const u8,
+    sub_path_w: [:0]const u16,
     options: Io.Dir.OpenOptions,
 ) Io.Dir.OpenError!Io.Dir {
-    const t: *Threaded = @ptrCast(@alignCast(userdata));
-    try t.checkCancel();
-
     const w = windows;
-    const sub_path_w_array = try w.sliceToPrefixedFileW(dir.handle, sub_path);
-    const sub_path_w = sub_path_w_array.span();
-
     // TODO remove some of these flags if options.access_sub_paths is false
     const base_flags = w.STANDARD_RIGHTS_READ | w.FILE_READ_ATTRIBUTES | w.FILE_READ_EA |
         w.SYNCHRONIZE | w.FILE_TRAVERSE;
@@ -2158,6 +2156,7 @@ fn dirOpenDirWindows(
     const open_reparse_point: w.DWORD = if (!options.follow_symlinks) w.FILE_OPEN_REPARSE_POINT else 0x0;
     var io_status_block: w.IO_STATUS_BLOCK = undefined;
     var result: Io.Dir = .{ .handle = undefined };
+    try t.checkCancel();
     const rc = w.ntdll.NtCreateFile(
         &result.handle,
         access_mask,
diff --git a/lib/std/posix.zig b/lib/std/posix.zig
index bb556be133..f708dfeaba 100644
--- a/lib/std/posix.zig
+++ b/lib/std/posix.zig
@@ -3769,7 +3769,6 @@ pub fn connect(sock: socket_t, sock_addr: *const sockaddr, len: socklen_t) Conne
             .SUCCESS => return,
             .ACCES => return error.AccessDenied,
             .PERM => return error.PermissionDenied,
-            .ADDRINUSE => return error.AddressInUse,
             .ADDRNOTAVAIL => return error.AddressUnavailable,
             .AFNOSUPPORT => return error.AddressFamilyUnsupported,
             .AGAIN, .INPROGRESS => return error.WouldBlock,
@@ -3779,7 +3778,7 @@ pub fn connect(sock: socket_t, sock_addr: *const sockaddr, len: socklen_t) Conne
             .CONNRESET => return error.ConnectionResetByPeer,
             .FAULT => unreachable, // The socket structure address is outside the user's address space.
             .INTR => continue,
-            .ISCONN => return error.AlreadyConnected, // The socket is already connected.
+            .ISCONN => @panic("AlreadyConnected"), // The socket is already connected.
             .HOSTUNREACH => return error.NetworkUnreachable,
             .NETUNREACH => return error.NetworkUnreachable,
             .NOTSOCK => unreachable, // The file descriptor sockfd does not refer to a socket.
diff --git a/lib/std/process/Child.zig b/lib/std/process/Child.zig
index 7ca919ca46..e49c5c4532 100644
--- a/lib/std/process/Child.zig
+++ b/lib/std/process/Child.zig
@@ -1084,16 +1084,24 @@ fn windowsCreateProcessPathExt(
     // or a version with a supported PATHEXT appended. We then try calling CreateProcessW
     // with the found versions in the appropriate order.
 
+    // In the future, child process execution needs to move to Io implementation.
+    // Under those conditions, here we will have access to lower level directory
+    // opening function knowing which implementation we are in. Here, we imitate
+    // that scenario.
+    var threaded: std.Io.Threaded = .init_single_threaded;
+    const io = threaded.io();
+
     var dir = dir: {
         // needs to be null-terminated
         try dir_buf.append(allocator, 0);
         defer dir_buf.shrinkRetainingCapacity(dir_path_len);
         const dir_path_z = dir_buf.items[0 .. dir_buf.items.len - 1 :0];
         const prefixed_path = try windows.wToPrefixedFileW(null, dir_path_z);
-        break :dir fs.cwd().openDirW(prefixed_path.span().ptr, .{ .iterate = true }) catch
-            return error.FileNotFound;
+        break :dir threaded.dirOpenDirWindows(.cwd(), prefixed_path.span(), .{
+            .iterate = true,
+        }) catch return error.FileNotFound;
     };
-    defer dir.close();
+    defer dir.close(io);
 
     // Add wildcard and null-terminator
     try app_buf.append(allocator, '*');
@@ -1127,7 +1135,7 @@ fn windowsCreateProcessPathExt(
             .Buffer = @constCast(app_name_wildcard.ptr),
         };
         const rc = windows.ntdll.NtQueryDirectoryFile(
-            dir.fd,
+            dir.handle,
             null,
             null,
             null,