fuse integration: add POSIX compliance test suite

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test/fuse_integration/sendfile_darwin.go

@@ -0,0 +1,43 @@
+//go:build darwin
+
+package fuse
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+// Sendfile support for macOS
+
+func sendfileTransfer(outFd int, inFd int, offset *int64, count int) (int, error) {
+	// macOS sendfile has different signature: sendfile(in_fd, out_fd, offset, len, hdtr, flags)
+	var off int64
+	if offset != nil {
+		off = *offset
+	}
+
+	length := int64(count)
+
+	_, _, errno := syscall.Syscall6(syscall.SYS_SENDFILE,
+		uintptr(inFd),                    // input fd
+		uintptr(outFd),                   // output fd
+		uintptr(off),                     // offset
+		uintptr(unsafe.Pointer(&length)), // length (in/out parameter)
+		0,                                // hdtr (headers/trailers)
+		0)                                // flags
+
+	if errno != 0 {
+		return 0, errno
+	}
+
+	// Update offset if provided
+	if offset != nil {
+		*offset += length
+	}
+
+	return int(length), nil
+}
+
+func isSendfileSupported() bool {
+	return true
+}