Make `OS.execute()` blocking by default if not specified

This makes `OS.execute()` calls quicker to set up when calling programs
in a blocking fashion.

core/bind/core_bind.cpp

@@ -1266,7 +1266,7 @@ void _OS::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("get_processor_count"), &_OS::get_processor_count);
 
 	ClassDB::bind_method(D_METHOD("get_executable_path"), &_OS::get_executable_path);
-	ClassDB::bind_method(D_METHOD("execute", "path", "arguments", "blocking", "output", "read_stderr"), &_OS::execute, DEFVAL(Array()), DEFVAL(false));
+	ClassDB::bind_method(D_METHOD("execute", "path", "arguments", "blocking", "output", "read_stderr"), &_OS::execute, DEFVAL(true), DEFVAL(Array()), DEFVAL(false));
 	ClassDB::bind_method(D_METHOD("kill", "pid"), &_OS::kill);
 	ClassDB::bind_method(D_METHOD("shell_open", "uri"), &_OS::shell_open);
 	ClassDB::bind_method(D_METHOD("get_process_id"), &_OS::get_process_id);

core/bind/core_bind.h

@@ -227,7 +227,7 @@ public:
 	int get_low_processor_usage_mode_sleep_usec() const;
 
 	String get_executable_path() const;
-	int execute(const String &p_path, const Vector<String> &p_arguments, bool p_blocking, Array p_output = Array(), bool p_read_stderr = false);
+	int execute(const String &p_path, const Vector<String> &p_arguments, bool p_blocking = true, Array p_output = Array(), bool p_read_stderr = false);
 
 	Error kill(int p_pid);
 	Error shell_open(String p_uri);

core/os/os.h

@@ -267,7 +267,7 @@ public:
 	virtual int get_low_processor_usage_mode_sleep_usec() const;
 
 	virtual String get_executable_path() const;
-	virtual Error execute(const String &p_path, const List<String> &p_arguments, bool p_blocking, ProcessID *r_child_id = NULL, String *r_pipe = NULL, int *r_exitcode = NULL, bool read_stderr = false, Mutex *p_pipe_mutex = NULL) = 0;
+	virtual Error execute(const String &p_path, const List<String> &p_arguments, bool p_blocking = true, ProcessID *r_child_id = NULL, String *r_pipe = NULL, int *r_exitcode = NULL, bool read_stderr = false, Mutex *p_pipe_mutex = NULL) = 0;
 	virtual Error kill(const ProcessID &p_pid) = 0;
 	virtual int get_process_id() const;
 	virtual void vibrate_handheld(int p_duration_ms = 500);

doc/classes/OS.xml

@@ -95,7 +95,7 @@
 			</argument>
 			<argument index="1" name="arguments" type="PoolStringArray">
 			</argument>
-			<argument index="2" name="blocking" type="bool">
+			<argument index="2" name="blocking" type="bool" default="true">
 			</argument>
 			<argument index="3" name="output" type="Array" default="[  ]">
 			</argument>

drivers/unix/os_unix.h

@@ -85,7 +85,7 @@ public:
 	virtual void delay_usec(uint32_t p_usec) const;
 	virtual uint64_t get_ticks_usec() const;
 
-	virtual Error execute(const String &p_path, const List<String> &p_arguments, bool p_blocking, ProcessID *r_child_id = NULL, String *r_pipe = NULL, int *r_exitcode = NULL, bool read_stderr = false, Mutex *p_pipe_mutex = NULL);
+	virtual Error execute(const String &p_path, const List<String> &p_arguments, bool p_blocking = true, ProcessID *r_child_id = NULL, String *r_pipe = NULL, int *r_exitcode = NULL, bool read_stderr = false, Mutex *p_pipe_mutex = NULL);
 	virtual Error kill(const ProcessID &p_pid);
 	virtual int get_process_id() const;
 

platform/javascript/os_javascript.h

@@ -141,7 +141,7 @@ public:
 	void run_async();
 	bool main_loop_iterate();
 
-	virtual Error execute(const String &p_path, const List<String> &p_arguments, bool p_blocking, ProcessID *r_child_id = NULL, String *r_pipe = NULL, int *r_exitcode = NULL, bool read_stderr = false, Mutex *p_pipe_mutex = NULL);
+	virtual Error execute(const String &p_path, const List<String> &p_arguments, bool p_blocking = true, ProcessID *r_child_id = NULL, String *r_pipe = NULL, int *r_exitcode = NULL, bool read_stderr = false, Mutex *p_pipe_mutex = NULL);
 	virtual Error kill(const ProcessID &p_pid);
 	virtual int get_process_id() const;
 

platform/uwp/os_uwp.h

@@ -205,7 +205,7 @@ public:
 	virtual void delay_usec(uint32_t p_usec) const;
 	virtual uint64_t get_ticks_usec() const;
 
-	virtual Error execute(const String &p_path, const List<String> &p_arguments, bool p_blocking, ProcessID *r_child_id = NULL, String *r_pipe = NULL, int *r_exitcode = NULL, bool read_stderr = false, Mutex *p_pipe_mutex = NULL);
+	virtual Error execute(const String &p_path, const List<String> &p_arguments, bool p_blocking = true, ProcessID *r_child_id = NULL, String *r_pipe = NULL, int *r_exitcode = NULL, bool read_stderr = false, Mutex *p_pipe_mutex = NULL);
 	virtual Error kill(const ProcessID &p_pid);
 
 	virtual bool has_environment(const String &p_var) const;

platform/windows/os_windows.h

@@ -359,7 +359,7 @@ public:
 	virtual void delay_usec(uint32_t p_usec) const;
 	virtual uint64_t get_ticks_usec() const;
 
-	virtual Error execute(const String &p_path, const List<String> &p_arguments, bool p_blocking, ProcessID *r_child_id = NULL, String *r_pipe = NULL, int *r_exitcode = NULL, bool read_stderr = false, Mutex *p_pipe_mutex = NULL);
+	virtual Error execute(const String &p_path, const List<String> &p_arguments, bool p_blocking = true, ProcessID *r_child_id = NULL, String *r_pipe = NULL, int *r_exitcode = NULL, bool read_stderr = false, Mutex *p_pipe_mutex = NULL);
 	virtual Error kill(const ProcessID &p_pid);
 	virtual int get_process_id() const;