I don't know why, but getppid() returns wrong result for me when application is started

AppRun.c.patch

@@ -41,17 +41,34 @@
  
      old_env = getenv("PYTHONPATH") ?: "";
      SET_NEW_ENV(new_pythonpath, appdir_s + strlen(old_env), "PYTHONPATH=%s/usr/share/pyshared/:%s", appdir, old_env);
-@@ -197,15 +208,12 @@
+@@ -196,16 +207,29 @@
+     /* Otherwise may get errors because Python cannot write __pycache__ bytecode cache */
      putenv("PYTHONDONTWRITEBYTECODE=1");
  
-     /* Run */
+-    /* Run */
 -    ret = execvp(exe, outargptrs);
--
++    /* Set pid & ppid */
++    pid_t pid = getpid();
++    pid_t ppid = getppid();
+ 
 -    int error = errno;
-+    execvp(exe, outargptrs);
++    int pid_len = snprintf(NULL, 0, "%d", pid);
++    int ppid_len = snprintf(NULL, 0, "%d", ppid);
  
 -    if (ret == -1)
 -        die("Error executing '%s': %s\n", exe, strerror(error));
++    char *s_pid = malloc(pid_len + 1);
++    snprintf(s_pid, pid_len + 1, "%d", pid);
++
++    char *s_ppid = malloc(ppid_len + 1);
++    snprintf(s_ppid, ppid_len + 1, "%d", ppid);
++
++    setenv("PID", s_pid, 1);
++    setenv("PPID", s_ppid, 1);
++
++    /* Run */
++    execvp(exe, outargptrs);
++
 +    free(optional_ld_library_path);
 +    if (optional_ld_preload)
 +        free(optional_ld_preload);
@@ -61,7 +78,7 @@
      free(usr_in_appdir);
      free(new_pythonhome);
      free(new_path);
-@@ -215,5 +223,16 @@
+@@ -215,5 +239,16 @@
      free(new_perllib);
      free(new_gsettings_schema_dir);
      free(new_qt_plugin_path);

env.c

@@ -43,6 +43,21 @@ void env_free(char* const *env) {
     free((char**)env);
 }
 
+pid_t get_parent_pid() {
+    pid_t ppid = 0;
+    char *s_ppid = getenv("PPID");
+
+    if(s_ppid) {
+        ppid = atoi(s_ppid);
+    }
+
+    if (!ppid) {
+        ppid = getppid();
+    }
+
+    return ppid;
+}
+
 static size_t get_number_of_variables(FILE *file, char **buffer, size_t *len) {
     size_t number = 0;
 
@@ -103,7 +118,7 @@ static char* const* read_env_from_process(pid_t pid) {
 }
 
 char* const* read_parent_env() {
-    pid_t ppid = getppid();
+    pid_t ppid = get_parent_pid();
     return read_env_from_process(ppid);
 }
 

env.h

@@ -3,6 +3,7 @@
 
 #include <unistd.h>
 
+pid_t get_parent_pid();
 char* const* read_parent_env();
 void env_free(char* const *env);
 

exec.c

@@ -79,7 +79,7 @@ static int exec_common(execve_func_t function, const char *filename, char* const
     DEBUG("filename %s, fullpath %s\n", filename, fullpath);
     char* const *env = envp;
     if (is_external_process(fullpath)) {
-        DEBUG("External process detected. Restoring env vars from parent %d\n", getppid());
+        DEBUG("External process detected. Restoring env vars from parent %d\n", get_parent_pid());
         env = read_parent_env();
         if (!env)
             env = envp;