class PluginImpl(object):

    ...

    def download_repomd(self):
        " May throw if repomd.xml does not exists at server "
        with open(os.devnull, 'w') as FNULL:
            return check_output([
                "wget", self.mtdt_url + "repomd.xml", "-O-"
            ], stderr=FNULL).decode("utf-8")

    ...

        def _sync(self, url, input_file, target):
        " this is exception safe (unless something unexpected will happen) "
        # if file that will be synced does not exists, this should be aborted
        if not os.path.isfile(input_file):
            check_output(["touch", input_file])
        try:
            zsync = Popen(["zsync", url, "-i", input_file, "-o",
                           target], stdout=PIPE, stderr=PIPE)
            outputs = zsync.communicate()
            if self._print_log:
                print(outputs[1].decode("utf-8"))
                print(outputs[0].decode("utf-8"))
        except CalledProcessError as ex:
            # print(str(ex), file=sys.stderr)
            # reverse rewriting existing if there was any
            try:
                check_output(["mv", target + ".zs-old", target])
            except:
                pass
        else:
            # cleanup
            check_output(["rm", "-rf", target + ".zs-old",
                          input_file if input_file != target else ""])
        return zsync.returncode

Section "InputClass"
	Identifier	"Trackpoint Wheel Emulation"
	MatchProduct	"TPPS/2 IBM TrackPoint|DualPoint Stick|Synaptics Inc. Composite TouchPad / TrackPoint|ThinkPad USB Keyboard with TrackPoint|USB Trackpoint pointing device|Composite TouchPad / TrackPoint"
	MatchDevicePath	"/dev/input/event*"
	Option		"EmulateWheel"		"true"
	Option		"EmulateWheelButton"	"2"
	Option		"Emulate3Buttons"	"false"
	Option		"XAxisMapping"		"6 7"
	Option		"YAxisMapping"		"4 5"
EndSection

$ machinectl shell

// gcc `pkg-config --libs --cflags glib-2.0` -g g_autoptr.c
#include <glib.h>

G_DEFINE_AUTOPTR_CLEANUP_FUNC (gchar, g_free);

void
print_elem (gpointer data,
            gpointer user_data)
{
  g_print ("GList: %s\n", (gchar *) data);
}

gint
main (gint   argc,
      gchar *argv[])
{
  g_autoptr(gchar) tmp = g_strdup ("Hello, I'm gchar!");
  g_autoptr(GList) lst = NULL;
  lst = g_list_append (lst, tmp);

  g_print ("gchar: %s\n", tmp);
  g_list_foreach (lst, (GFunc) print_elem, NULL);

  return 0;
}

$ valgrind --tool=memcheck --leak-check=full ./g_autoptr
==9620== HEAP SUMMARY:
==9620==     in use at exit: 2,094 bytes in 6 blocks
==9620==   total heap usage: 22 allocs, 16 frees, 68,943 bytes allocated
==9620== 
==9620== LEAK SUMMARY:
==9620==    definitely lost: 0 bytes in 0 blocks
==9620==    indirectly lost: 0 bytes in 0 blocks
==9620==      possibly lost: 0 bytes in 0 blocks
==9620==    still reachable: 2,094 bytes in 6 blocks
==9620==         suppressed: 0 bytes in 0 blocks

$ valgrind --tool=memcheck --leak-check=full ./no_g_autoptr
==9705== HEAP SUMMARY:
==9705==     in use at exit: 2,136 bytes in 8 blocks
==9705==   total heap usage: 22 allocs, 14 frees, 68,943 bytes allocated
==9705== 
==9705== 42 (24 direct, 18 indirect) bytes in 1 blocks are definitely lost in loss record 7 of 8
==9705==    at 0x4C2AC10: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==9705==    by 0x4E82769: g_malloc (in /usr/lib64/libglib-2.0.so.0.4501.0)
==9705==    by 0x4E99DC2: g_slice_alloc (in /usr/lib64/libglib-2.0.so.0.4501.0)
==9705==    by 0x4E78EE3: g_list_append (in /usr/lib64/libglib-2.0.so.0.4501.0)
==9705==    by 0x400848: main (no_g_autoptr.c:16)
==9705== 
==9705== LEAK SUMMARY:
==9705==    definitely lost: 24 bytes in 1 blocks
==9705==    indirectly lost: 18 bytes in 1 blocks
==9705==      possibly lost: 0 bytes in 0 blocks
==9705==    still reachable: 2,094 bytes in 6 blocks
==9705==         suppressed: 0 bytes in 0 blocks

{
  g_autoptr(GObject) object;
  g_autoptr(gchar) tmp;
  g_auto(GQueue) queue;

  g_queue_init (&queue);
  object = g_object_new (...);
  tmp = g_strdup_printf (...);

  // no free required
}

#define GS_DEFINE_CLEANUP_FUNCTION0(Type, name, func) \
  static inline void name (void *v) \
  { \
    if (*(Type*)v) \
      func (*(Type*)v); \
  }
#define _cleanup_error_free_ __attribute__ ((cleanup(gs_local_free_error)))
GS_DEFINE_CLEANUP_FUNCTION0(GError*, gs_local_free_error, g_error_free)

_cleanup_error_free_ GError *error = NULL;

char *c;
&c = "Hello";

char *c;
strdup(c) = "Hello";

[brain@X1Carbon fedora]$ cowsay "${subj}"
 _________________________________________ 
/ А сегодня у меня Birthday! \
\ ;)                                      /
 ----------------------------------------- 
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||