├── images
    ├── pem.gif
    ├── hass.png
    ├── mqtt.png
    ├── mounted.jpg
    ├── pemlog.png
    ├── schematics.png
    ├── esp32pem_out.png
    ├── adeleq_02-553_DIG.jpg
    ├── ds18b20_connection.png
    └── pulse_measurement.png
├── README.md
├── esp32_powermeter_mqtt
    └── esp32_powermeter_mqtt.ino
└── LICENSE


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/README.md:
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  1 | # Power Meter with mqtt-for devices with pulse output
  2 | 
  3 | 
  4 | ## About
  5 | 
  6 |  This project presents a simple solution for measuring the energy consumption of a house. The key element is a cheap energy monitor with pulse output, connected to an [ESP32 WROOM 32 board](https://docs.espressif.com/projects/esp-idf/en/latest/hw-reference/modules-and-boards.html#esp-modules-and-boards-esp32-wroom-32). This, over WiFi using mqtt protocol can be easily connected to a home automation system to report:
  7 | - instant power (in Watt);
  8 | - total power consumption (in kWh);
  9 | - Device temperature (in Celsius) using a DS18b20 temperature sensor.
 10 | 
 11 | OTA support is enabled, after the first software upload, the ESP will available for updates on the local network over [Arduino IDE](https://www.arduino.cc/en/main/software).
 12 | 
 13 | ## Hardware Components
 14 | 
 15 | ### ESP 32 board
 16 | [ESP32 WROOM 32 board](https://docs.espressif.com/projects/esp-idf/en/latest/hw-reference/modules-and-boards.html#esp-modules-and-boards-esp32-wroom-32)
 17 | 
 18 | ### The Power Meter
 19 | 
 20 | The power meter [adeleq_02-553_DIG](https://www.dedeman.ro/ro/contor-monofazic-digital-45a-1m-02-553/dig/p/1030357) operating range is 0.05A-45A, and (the most important part) provide 2000 impulses / kWh. Emitted pulses for detections have ~90 ms pulse width. The output is open collector, operating voltage, from 5-24V. In this case, the ESP32 supply provides 3.3V, but this is not a limitation. Other variants are available on the market, usually, the difference is the accuracy (i.e. pulses / kWh are only 1000 instead of 2000). 
 21 | 
 22 | <h1 align="center">
 23 |   <a name="Pulse Output" href=""><img src="images/adeleq_02-553_DIG.jpg" alt="300" width="300"></a>
 24 |   <a name="Pulse Output" href=""><img src="images/pem.gif" alt="300" width="300"></a>
 25 | </h1>
 26 | Below a sample picture for the output, where a light bulb (~53W) is connected to the power meter.
 27 | The measured pulse between the two detections is about 30.71s, which leads to a value measured of ~58.61 Watts.
 28 | 
 29 | ```
 30 | Conversion from kWh to Watts, measured with a sensor of 2000 pulses/ kWh:
 31 | (<kilo Watt to Watt>*<Hour in secounds>/<impuse number>)/<time measured between pulses> 
 32 | =>(1000*3600/2000)/31.71 => 58.71W
 33 | ```
 34 | 
 35 | <h1 align="center">
 36 |   <a name="Pulse Output" href=""><img src="images/pulse_measurement.png" alt="" width="800"></a>
 37 | </h1>
 38 | 
 39 | ### The temperature sensor
 40 | [DS18b20](https://datasheets.maximintegrated.com/en/ds/DS18B20.pdf) is a fast digital thermometer using 1-Wire protocol. The usual connection diagram is with a 4.7 kOhm pull-up resistor.
 41 | 
 42 | ### Connection diagramm
 43 | 
 44 | Below the wiring diagram, made with [Easyeda](https://easyeda.com/) tool. In noisy environments, the recommendation is to add a 33pf condensator between ground and energy sensor input pins (to avoid sporadic interrupts).
 45 | <h1 align="center">
 46 |   <a name="Pulse Output" href=""><img src="images/schematics.png" alt="" width="400"></a>
 47 | </h1>
 48 | 
 49 | 
 50 | ### Final integration
 51 | <table>
 52 | <h1 align="left">
 53 | <tr>
 54 |   <th>
 55 |   <a name="Pulse Output" href=""><img src="images/esp32pem_out.png" alt="400" width="400"></a>
 56 |   </th>
 57 |   <th>
 58 |   <a name="Pulse Outputx" href=""><img src="images/mounted.jpg" alt="400" width="400"></a>
 59 |   </th>
 60 | </tr>
 61 | </h1>
 62 | </table>
 63 | 
 64 | # How to use
 65 | 
 66 | Clone the repository, update the .ino file in [Arduino IDE](https://www.arduino.cc/en/main/software) with your local WiFi / mqtt configuration.
 67 | 
 68 | >Note: you need to install the following libraries before compile: [PubSubClient](https://www.arduino.cc/reference/en/libraries/pubsubclient/) - for mqtt client, [OneWire](https://www.arduino.cc/reference/en/libraries/onewire/) - for 1-wire communication and [DallasTemerature](https://www.arduino.cc/reference/en/libraries/dallastemperature/) - for DS18b20 temperature sensor.
 69 | 
 70 | >Note: to enable serial debugging, uncomment the following line: #define DEBUG
 71 | 
 72 | >Note: once flashed the the ESP32, after a succesfull connect to your WiFi, OTA update become available. This means the device can be mounted and the software can be flashed / updated over the your local network (see the new port under ArduinoIDE->tools->port->network ports).
 73 | 
 74 | ```
 75 | /*mqtt declarations*/
 76 | const char* mqtt_server = "<IP OF THE MQTT SERVER>";
 77 | const char* mqtt_user = "<USER NAME>";
 78 | const char* mqtt_password = "<PASSWORD>";
 79 | ...
 80 | /* SSID and Password of WiFi router */
 81 | const char* ssid = "<ROUTER SSID>";
 82 | const char* password = "<ROUTER PASSWORD>";
 83 | ```
 84 | 
 85 | Upload the code in the [ESP32 WROOM 32 board](https://docs.espressif.com/projects/esp-idf/en/latest/hw-reference/modules-and-boards.html#esp-modules-and-boards-esp32-wroom-32) over USB, wire the board accordingly to the schematics. The output will be something similar on the mqtt topics:
 86 | <h1 align="center">
 87 | <a name="Pulse Output" href=""><img src="images/mqtt.png" alt="400" width="400"></a>
 88 | </h1>
 89 | 
 90 | ~~~
 91 | Additionally the following mqtt commands can be used:
 92 | - topic: /pulseenergymonitor/cmd
 93 | - payload: c / r
 94 |   c - clear kWh information
 95 |   r - reset the device
 96 | ~~~
 97 | 
 98 | ## Home Assistant integration
 99 | 
100 | [Home Assistant](https://www.home-assistant.io/) is an open source automatization system, with a high number of component integratios. Is a good choise for complex IOT and DIY smart home atomatization. Below a panel component and a log file which shows the sensor information and energy consumption.
101 | <h1 align="center">
102 | <a name="Pulse Output" href=""><img src="images/pemlog.png" alt="400" width="1024"></a>
103 | <a name="Pulse Output" href=""><img src="images/hass.png" alt="400" width="400"></a>
104 | </h1>
105 | 
106 | Paste the following lines in the configuration.yaml file:
107 | ```
108 | sensor:
109 |   - platform: mqtt
110 |     state_topic: "/pulseenergymonitor/watts"
111 |     name: "Pulse Energy Monitor"
112 |     icon: mdi:gauge
113 |     unit_of_measurement: "W"
114 |   - platform: mqtt
115 |     state_topic: "/pulseenergymonitor/kWh"
116 |     name: "PEM kWh"
117 |     icon: mdi:gauge
118 |     unit_of_measurement: "kWh"
119 | ```
120 | Energy consumption measurement has a specific component in Home Assistant, the [utility meter](https://www.home-assistant.io/integrations/utility_meter/), past into configuration.yaml file.
121 | ```
122 | ##################################
123 | # Utility meter
124 | ##################################
125 | 
126 | utility_meter:
127 |   daily_energy:
128 |     source: sensor.pem_kwh
129 |     cycle: daily
130 |   weekly_energy:
131 |     source: sensor.pem_kwh
132 |     cycle: weekly
133 |   monthly_energy:
134 |     source: sensor.pem_kwh
135 |     cycle: monthly
136 | ```
137 | 
138 | /Enjoy.
139 | 


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/esp32_powermeter_mqtt/esp32_powermeter_mqtt.ino:
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  1 | /***************************************************************************
  2 |  * Power Meter - for devices with pulse output 
  3 |  * 
  4 |  * Host device is an ESP32 WROOM 32 board
  5 |  * A DS18d20 sensor delivers accurate temperature manasurements  
  6 |  * 
  7 |  * The device is connected to WiFi, enableing (simple) OTA 
  8 |  * updates over Arduino IDE.
  9 |  * 
 10 |  * The mqtt client pushes on the /pulseenergymonitor/# topics the:
 11 |  * - instant Watts measurements
 12 |  * - counted kWh (RAM)
 13 |  * - instant temperature of the board
 14 |  * NOTE: replace "<...>" fields with your data
 15 |  ***************************************************************************/
 16 |  
 17 | #include <WiFi.h>
 18 | #include <PubSubClient.h>
 19 | #include <ArduinoOTA.h>
 20 | #include <OneWire.h>
 21 | #include <DallasTemperature.h>
 22 | 
 23 | 
 24 | /*#define DEBUG*/                 /* activates debug on serial line*/
 25 | #define IN_PIN_PEM 18             /* input pin for pulse sensor */
 26 | #define IN_PIN_TMP 2              /* input pin for DS18d20 temperature sensor */
 27 | #define ISR_TYPE FALLING          /* isr triggering mode */
 28 | #define HOUR 3600.0               /* hour as constant */
 29 | #define PULSES_KWH_RES 0.5        /* 1 KW = 1000W, power meter has 2000 inpulses resolution */
 30 | #define SECOUND_ISR_PERIOD 0.09   /* pulse period is ~90 ms, used to ignore secound interrupt arrival bug*/
 31 | #define MAX_POWER 7040            /* for a peek of 32A => 7040W, ignor higher measurements */
 32 | 
 33 | /*mqtt declarations*/
 34 | const char* mqtt_server = "<IP OF THE MQTT SERVER>";
 35 | const char* mqtt_user = "<USER NAME>";
 36 | const char* mqtt_password = "<PASSWORD>";
 37 | const char* power_topic = "/pulseenergymonitor/watts";
 38 | const char* kWh_topic = "/pulseenergymonitor/kWh";
 39 | const char* tmp_topic = "/pulseenergymonitor/tmp";
 40 | const char* cmd_topic = "/pulseenergymonitor/cmd";
 41 | const char* lwt_topic = "/pulseenergymonitor/lwt";
 42 | const char* lwt_msg_off = "OFF";
 43 | const char* lwt_msg_on = "ON";
 44 | 
 45 | /* SSID and Password of WiFi router */
 46 | const char* ssid = "<ROUTER SSID>";
 47 | const char* password = "<ROUTER PASSWORD>";
 48 | 
 49 | 
 50 | /* variables an */
 51 | WiFiClient espClient;
 52 | PubSubClient client(espClient);
 53 | OneWire ds(IN_PIN_TMP);
 54 | DallasTemperature DS18B20(&ds); 
 55 | 
 56 | const double MAX_DELAY = 60;              /*period after mqtt will send the zero value*/
 57 | volatile double dPulsePeriod = 0.0;       /*period measured  between 2 impulses*/
 58 | volatile double dPower = 0.0;             /*instant power, in W*/
 59 | volatile boolean bPulseDetected = false;  /*first pulse detetcted*/
 60 | volatile unsigned long ulStartTime = 0;   /*time measured when firts pulse from pulsed energy sensor fires*/
 61 | volatile unsigned long ulCurrentMillis = 0;   /*temporary variable for storing millis value at `isr()` function start*/
 62 | volatile double dKWh=0.0;                 /*cumulative kWh*/
 63 | volatile unsigned int uiIsrCount = 0;     /*counter to hold the number of measirements*/
 64 | volatile double dTotalW = 0.0;            /*total Watts measured over a raporting cycle on mqtt*/
 65 | unsigned int uiCount = 0;                 /*counter used to measure the secounds in the main loop*/
 66 | 
 67 | 
 68 | /***********************************************************
 69 |  * interrupt routine, 
 70 |  * used to measure the pulse length and calculate the power
 71 | ************************************************************/
 72 | void IRAM_ATTR isr()
 73 | {
 74 |   ulCurrentMillis = millis();
 75 |   
 76 |   /*test if first pulse arrived*/
 77 |   if (bPulseDetected == false)
 78 |   {
 79 |       /*get current time*/
 80 |       ulStartTime = ulCurrentMillis;
 81 |       bPulseDetected = true;
 82 |   }
 83 |   else  /*secound pulse, test if isr issue*/
 84 |   {
 85 |     /*time measured in secounds, from the last measurement*/
 86 |     dPulsePeriod = (double)(ulCurrentMillis-ulStartTime)/1000.0; 
 87 |     
 88 |     /*ignore, if period is shorther than pulse legth ~90ms*/
 89 |     if (dPulsePeriod <= SECOUND_ISR_PERIOD)
 90 |     {
 91 |       /*ignor measurement*/
 92 |       dPulsePeriod = 0.0;
 93 | 
 94 |     }
 95 |     else /*no interrupt issue, compute the power*/
 96 |     {
 97 | 
 98 |       uiIsrCount++;
 99 |       dPower = (PULSES_KWH_RES/(double)dPulsePeriod)*HOUR;
100 | 
101 |       /*filter wrong readings*/
102 |       if (dPower > MAX_POWER)
103 |       {
104 |         /*reading error, reset power*/
105 |         dPower = 0.0;
106 |         
107 |       }
108 | 
109 |       /*cumulative power*/
110 |       dTotalW += dPower;
111 |         
112 |       /*update kWh*/
113 |       dKWh += ((dPulsePeriod/HOUR)*(dPower/1000.0));
114 |       
115 |       /*get current time*/
116 |       ulStartTime = ulCurrentMillis;
117 |       bPulseDetected = true;
118 | 
119 |     }
120 | 
121 |   }
122 | }
123 | 
124 | /***********************************************
125 |  * MQTT receiver callback
126 |  * coomad list, on /pulseenergymonitor/cmd
127 |  * c - clear RAM stored kWh
128 |  * r - reset the system
129 | ************************************************/
130 | void callback(char* topic, byte* payload, unsigned int length)
131 | {
132 |   byte comma = 0;
133 | #ifdef DEBUG
134 |   Serial.print("Message in topic: ");
135 |   Serial.println(topic);
136 |   Serial.print("Message ");
137 | 
138 |   for(int i = 0; i < length; i++) 
139 |   {
140 |     Serial.print((char)payload[i]);
141 |   }
142 | 
143 |   Serial.println("");
144 | #endif
145 | 
146 |   /*reciver handler*/
147 |   if ((char)payload[0] == 'c')
148 |   {
149 |     /*reset kWh counter*/
150 |     dKWh = 0.0;  
151 |   }
152 |   else if ((char)payload[0] == 'r')
153 |   {
154 | #ifdef DEBUG
155 |     Serial.println("Warm Restart");
156 | #endif
157 |     ESP.restart();
158 |   }
159 | 
160 | #ifdef DEBUG
161 |   Serial.println();
162 | #endif
163 | 
164 | }
165 | 
166 | /***************************************
167 |  * read temperature from DS18B20 sensor
168 | ****************************************/
169 | float getTemperature() {
170 |   float tempC;
171 |   DS18B20.requestTemperatures(); 
172 |   tempC = DS18B20.getTempCByIndex(0);
173 | 
174 |   return tempC;
175 | }
176 | 
177 | 
178 | /***************************************
179 |  * init routine
180 | ****************************************/
181 | void setup() 
182 | {
183 | #ifdef DEBUG
184 |   Serial.begin(115200);
185 |   Serial.println("Scanning...");
186 | #endif
187 | 
188 |   /*set pin as output*/
189 |   pinMode(IN_PIN_PEM, INPUT_PULLDOWN);
190 | 
191 |   /*attch function to isr routine*/
192 |   attachInterrupt(IN_PIN_PEM, isr, ISR_TYPE);
193 | 
194 |   /*init temparature sensor*/
195 |   DS18B20.begin();
196 | 
197 |   /*Connect to your WiFi router*/
198 |   WiFi.begin(ssid, password);     
199 | #ifdef DEBUG
200 |   Serial.println("");
201 | #endif
202 | 
203 |   /*Wait for connection*/
204 |   while (WiFi.status() != WL_CONNECTED) 
205 |   {
206 |     delay(500);
207 | #ifdef DEBUG
208 |     Serial.print(".");
209 | #endif
210 | 
211 |   }
212 | 
213 |   /*set-up mqtt*/
214 |   client.setServer(mqtt_server, 1883);
215 |   client.setCallback(callback);
216 | 
217 |   /*connect to mqtt server, retry if needed*/
218 |   while (!client.connected()) 
219 |   {
220 | #ifdef DEBUG
221 |     Serial.println("Connecting to MQTT...");
222 | #endif
223 |     if(client.connect("pulseenergymonitor", mqtt_user, mqtt_password,lwt_topic,0,0,lwt_msg_off )) 
224 |     {
225 | #ifdef DEBUG
226 |      Serial.println("Connected to MQTT");
227 | #endif
228 |      client.publish(lwt_topic, lwt_msg_on, true);
229 |     }
230 |     else
231 |     {
232 | #ifdef DEBUG
233 |       Serial.print("failed state ");
234 |       Serial.print(client.state());
235 | #endif
236 |       delay(2000);
237 |     }
238 |   }
239 | 
240 |   /*subscribe for commands*/
241 |   client.subscribe(cmd_topic);
242 | 
243 |   /*OTA*/
244 |     ArduinoOTA
245 |     .onStart([]() {
246 |       String type;
247 |       if (ArduinoOTA.getCommand() == U_FLASH)
248 |         type = "sketch";
249 |       else /* U_SPIFFS*/
250 |         type = "filesystem";
251 | #ifdef DEBUG
252 |       Serial.println("Start updating " + type);
253 | #endif
254 |     })
255 |     .onEnd([]() {
256 | #ifdef DEBUG
257 |       Serial.println("\nEnd");
258 | #endif
259 |     })
260 |     .onProgress([](unsigned int progress, unsigned int total) {
261 | #ifdef DEBUG
262 |       Serial.printf("Progress: %u%%\r", (progress / (total / 100)));
263 | #endif
264 |     })
265 |     .onError([](ota_error_t error) {
266 | #ifdef DEBUG
267 |       Serial.printf("Error[%u]: ", error);
268 |       if (error == OTA_AUTH_ERROR) Serial.println("Auth Failed");
269 |       else if (error == OTA_BEGIN_ERROR) Serial.println("Begin Failed");
270 |       else if (error == OTA_CONNECT_ERROR) Serial.println("Connect Failed");
271 |       else if (error == OTA_RECEIVE_ERROR) Serial.println("Receive Failed");
272 |       else if (error == OTA_END_ERROR) Serial.println("End Failed");
273 | #endif
274 |     });
275 | 
276 |   ArduinoOTA.begin();
277 | 
278 | #ifdef DEBUG
279 |   Serial.println("Ready");
280 |   Serial.print("IP address: ");
281 |   Serial.println(WiFi.localIP());
282 | #endif
283 |   
284 |   
285 | }
286 | 
287 | 
288 | /*********************************
289 |  * Main loop
290 | **********************************/
291 | void loop() 
292 | {
293 | 
294 |   client.loop();
295 |   ArduinoOTA.handle();
296 | 
297 | #ifdef DEBUG
298 |   Serial.printf(String(dPulsePeriod).c_str());
299 |   Serial.printf(" , ");
300 |   Serial.printf(String(dPower).c_str());
301 |   Serial.printf("\n");
302 | #endif
303 | 
304 |   /*run if we have a measurement*/
305 |   if (dTotalW > 0.0)
306 |   {
307 |     /*compute average*/
308 |     dPower = dTotalW / uiIsrCount ;
309 | 
310 |     /*publis data over mqtt*/
311 |     client.publish(power_topic, String(dPower).c_str(), true);
312 |     client.publish(kWh_topic, String(dKWh).c_str(), true);
313 |     client.publish(tmp_topic, String(getTemperature()).c_str(), true);
314 |     
315 |     /*delete accumulated values, for new measurement*/
316 |     dPower = 0.0;
317 |     dTotalW = 0.0;
318 |     uiIsrCount = 0;
319 | 
320 |     /*reset cycle counter */
321 |     uiCount=1;
322 | 
323 |   }
324 | 
325 | 
326 |   /*when timeout on measurement, clear mqtt values*/
327 |   if (((uiCount % (uint (MAX_DELAY))) == 0))
328 |   {
329 |     dPower = 0.0;
330 |     dPulsePeriod = 0.0;
331 |     dTotalW = 0.0;
332 |     uiIsrCount = 0.0;
333 | 
334 |     /*no measurement, clear the values*/
335 |     client.publish(power_topic, String(dPower).c_str(), true);
336 |     client.publish(kWh_topic, String(dKWh).c_str(), true);
337 |     client.publish(tmp_topic, String(getTemperature()).c_str(), true); 
338 |   }
339 | 
340 |   /*reconect on Mqtt loss*/
341 |   if (client.state()< 0)
342 |   {
343 | #ifdef DEBUG
344 |     Serial.println("No MQTT Connection, reconnect");
345 | #endif
346 | 
347 |     delay (3000);
348 |     setup();  
349 |   }
350 | 
351 |   /*wait, time base for checking the measurements*/
352 |   delay(1000);
353 | 
354 |   /*increment cycle counter */
355 |   uiCount++;
356 |   
357 | }
358 | 


--------------------------------------------------------------------------------
/LICENSE:
--------------------------------------------------------------------------------
  1 |                     GNU GENERAL PUBLIC LICENSE
  2 |                        Version 3, 29 June 2007
  3 | 
  4 |  Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
  5 |  Everyone is permitted to copy and distribute verbatim copies
  6 |  of this license document, but changing it is not allowed.
  7 | 
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 13 |   The licenses for most software and other practical works are designed
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 15 | the GNU General Public License is intended to guarantee your freedom to
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 18 | GNU General Public License for most of our software; it applies also to
 19 | any other work released this way by its authors.  You can apply it to
 20 | your programs, too.
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 68 |   The precise terms and conditions for copying, distribution and
 69 | modification follow.
 70 | 
 71 |                        TERMS AND CONDITIONS
 72 | 
 73 |   0. Definitions.
 74 | 
 75 |   "This License" refers to version 3 of the GNU General Public License.
 76 | 
 77 |   "Copyright" also means copyright-like laws that apply to other kinds of
 78 | works, such as semiconductor masks.
 79 | 
 80 |   "The Program" refers to any copyrightable work licensed under this
 81 | License.  Each licensee is addressed as "you".  "Licensees" and
 82 | "recipients" may be individuals or organizations.
 83 | 
 84 |   To "modify" a work means to copy from or adapt all or part of the work
 85 | in a fashion requiring copyright permission, other than the making of an
 86 | exact copy.  The resulting work is called a "modified version" of the
 87 | earlier work or a work "based on" the earlier work.
 88 | 
 89 |   A "covered work" means either the unmodified Program or a work based
 90 | on the Program.
 91 | 
 92 |   To "propagate" a work means to do anything with it that, without
 93 | permission, would make you directly or secondarily liable for
 94 | infringement under applicable copyright law, except executing it on a
 95 | computer or modifying a private copy.  Propagation includes copying,
 96 | distribution (with or without modification), making available to the
 97 | public, and in some countries other activities as well.
 98 | 
 99 |   To "convey" a work means any kind of propagation that enables other
100 | parties to make or receive copies.  Mere interaction with a user through
101 | a computer network, with no transfer of a copy, is not conveying.
102 | 
103 |   An interactive user interface displays "Appropriate Legal Notices"
104 | to the extent that it includes a convenient and prominently visible
105 | feature that (1) displays an appropriate copyright notice, and (2)
106 | tells the user that there is no warranty for the work (except to the
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110 | menu, a prominent item in the list meets this criterion.
111 | 
112 |   1. Source Code.
113 | 
114 |   The "source code" for a work means the preferred form of the work
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117 | 
118 |   A "Standard Interface" means an interface that either is an official
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120 | interfaces specified for a particular programming language, one that
121 | is widely used among developers working in that language.
122 | 
123 |   The "System Libraries" of an executable work include anything, other
124 | than the work as a whole, that (a) is included in the normal form of
125 | packaging a Major Component, but which is not part of that Major
126 | Component, and (b) serves only to enable use of the work with that
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128 | implementation is available to the public in source code form.  A
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130 | (kernel, window system, and so on) of the specific operating system
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133 | 
134 |   The "Corresponding Source" for a work in object code form means all
135 | the source code needed to generate, install, and (for an executable
136 | work) run the object code and to modify the work, including scripts to
137 | control those activities.  However, it does not include the work's
138 | System Libraries, or general-purpose tools or generally available free
139 | programs which are used unmodified in performing those activities but
140 | which are not part of the work.  For example, Corresponding Source
141 | includes interface definition files associated with source files for
142 | the work, and the source code for shared libraries and dynamically
143 | linked subprograms that the work is specifically designed to require,
144 | such as by intimate data communication or control flow between those
145 | subprograms and other parts of the work.
146 | 
147 |   The Corresponding Source need not include anything that users
148 | can regenerate automatically from other parts of the Corresponding
149 | Source.
150 | 
151 |   The Corresponding Source for a work in source code form is that
152 | same work.
153 | 
154 |   2. Basic Permissions.
155 | 
156 |   All rights granted under this License are granted for the term of
157 | copyright on the Program, and are irrevocable provided the stated
158 | conditions are met.  This License explicitly affirms your unlimited
159 | permission to run the unmodified Program.  The output from running a
160 | covered work is covered by this License only if the output, given its
161 | content, constitutes a covered work.  This License acknowledges your
162 | rights of fair use or other equivalent, as provided by copyright law.
163 | 
164 |   You may make, run and propagate covered works that you do not
165 | convey, without conditions so long as your license otherwise remains
166 | in force.  You may convey covered works to others for the sole purpose
167 | of having them make modifications exclusively for you, or provide you
168 | with facilities for running those works, provided that you comply with
169 | the terms of this License in conveying all material for which you do
170 | not control copyright.  Those thus making or running the covered works
171 | for you must do so exclusively on your behalf, under your direction
172 | and control, on terms that prohibit them from making any copies of
173 | your copyrighted material outside their relationship with you.
174 | 
175 |   Conveying under any other circumstances is permitted solely under
176 | the conditions stated below.  Sublicensing is not allowed; section 10
177 | makes it unnecessary.
178 | 
179 |   3. Protecting Users' Legal Rights From Anti-Circumvention Law.
180 | 
181 |   No covered work shall be deemed part of an effective technological
182 | measure under any applicable law fulfilling obligations under article
183 | 11 of the WIPO copyright treaty adopted on 20 December 1996, or
184 | similar laws prohibiting or restricting circumvention of such
185 | measures.
186 | 
187 |   When you convey a covered work, you waive any legal power to forbid
188 | circumvention of technological measures to the extent such circumvention
189 | is effected by exercising rights under this License with respect to
190 | the covered work, and you disclaim any intention to limit operation or
191 | modification of the work as a means of enforcing, against the work's
192 | users, your or third parties' legal rights to forbid circumvention of
193 | technological measures.
194 | 
195 |   4. Conveying Verbatim Copies.
196 | 
197 |   You may convey verbatim copies of the Program's source code as you
198 | receive it, in any medium, provided that you conspicuously and
199 | appropriately publish on each copy an appropriate copyright notice;
200 | keep intact all notices stating that this License and any
201 | non-permissive terms added in accord with section 7 apply to the code;
202 | keep intact all notices of the absence of any warranty; and give all
203 | recipients a copy of this License along with the Program.
204 | 
205 |   You may charge any price or no price for each copy that you convey,
206 | and you may offer support or warranty protection for a fee.
207 | 
208 |   5. Conveying Modified Source Versions.
209 | 
210 |   You may convey a work based on the Program, or the modifications to
211 | produce it from the Program, in the form of source code under the
212 | terms of section 4, provided that you also meet all of these conditions:
213 | 
214 |     a) The work must carry prominent notices stating that you modified
215 |     it, and giving a relevant date.
216 | 
217 |     b) The work must carry prominent notices stating that it is
218 |     released under this License and any conditions added under section
219 |     7.  This requirement modifies the requirement in section 4 to
220 |     "keep intact all notices".
221 | 
222 |     c) You must license the entire work, as a whole, under this
223 |     License to anyone who comes into possession of a copy.  This
224 |     License will therefore apply, along with any applicable section 7
225 |     additional terms, to the whole of the work, and all its parts,
226 |     regardless of how they are packaged.  This License gives no
227 |     permission to license the work in any other way, but it does not
228 |     invalidate such permission if you have separately received it.
229 | 
230 |     d) If the work has interactive user interfaces, each must display
231 |     Appropriate Legal Notices; however, if the Program has interactive
232 |     interfaces that do not display Appropriate Legal Notices, your
233 |     work need not make them do so.
234 | 
235 |   A compilation of a covered work with other separate and independent
236 | works, which are not by their nature extensions of the covered work,
237 | and which are not combined with it such as to form a larger program,
238 | in or on a volume of a storage or distribution medium, is called an
239 | "aggregate" if the compilation and its resulting copyright are not
240 | used to limit the access or legal rights of the compilation's users
241 | beyond what the individual works permit.  Inclusion of a covered work
242 | in an aggregate does not cause this License to apply to the other
243 | parts of the aggregate.
244 | 
245 |   6. Conveying Non-Source Forms.
246 | 
247 |   You may convey a covered work in object code form under the terms
248 | of sections 4 and 5, provided that you also convey the
249 | machine-readable Corresponding Source under the terms of this License,
250 | in one of these ways:
251 | 
252 |     a) Convey the object code in, or embodied in, a physical product
253 |     (including a physical distribution medium), accompanied by the
254 |     Corresponding Source fixed on a durable physical medium
255 |     customarily used for software interchange.
256 | 
257 |     b) Convey the object code in, or embodied in, a physical product
258 |     (including a physical distribution medium), accompanied by a
259 |     written offer, valid for at least three years and valid for as
260 |     long as you offer spare parts or customer support for that product
261 |     model, to give anyone who possesses the object code either (1) a
262 |     copy of the Corresponding Source for all the software in the
263 |     product that is covered by this License, on a durable physical
264 |     medium customarily used for software interchange, for a price no
265 |     more than your reasonable cost of physically performing this
266 |     conveying of source, or (2) access to copy the
267 |     Corresponding Source from a network server at no charge.
268 | 
269 |     c) Convey individual copies of the object code with a copy of the
270 |     written offer to provide the Corresponding Source.  This
271 |     alternative is allowed only occasionally and noncommercially, and
272 |     only if you received the object code with such an offer, in accord
273 |     with subsection 6b.
274 | 
275 |     d) Convey the object code by offering access from a designated
276 |     place (gratis or for a charge), and offer equivalent access to the
277 |     Corresponding Source in the same way through the same place at no
278 |     further charge.  You need not require recipients to copy the
279 |     Corresponding Source along with the object code.  If the place to
280 |     copy the object code is a network server, the Corresponding Source
281 |     may be on a different server (operated by you or a third party)
282 |     that supports equivalent copying facilities, provided you maintain
283 |     clear directions next to the object code saying where to find the
284 |     Corresponding Source.  Regardless of what server hosts the
285 |     Corresponding Source, you remain obligated to ensure that it is
286 |     available for as long as needed to satisfy these requirements.
287 | 
288 |     e) Convey the object code using peer-to-peer transmission, provided
289 |     you inform other peers where the object code and Corresponding
290 |     Source of the work are being offered to the general public at no
291 |     charge under subsection 6d.
292 | 
293 |   A separable portion of the object code, whose source code is excluded
294 | from the Corresponding Source as a System Library, need not be
295 | included in conveying the object code work.
296 | 
297 |   A "User Product" is either (1) a "consumer product", which means any
298 | tangible personal property which is normally used for personal, family,
299 | or household purposes, or (2) anything designed or sold for incorporation
300 | into a dwelling.  In determining whether a product is a consumer product,
301 | doubtful cases shall be resolved in favor of coverage.  For a particular
302 | product received by a particular user, "normally used" refers to a
303 | typical or common use of that class of product, regardless of the status
304 | of the particular user or of the way in which the particular user
305 | actually uses, or expects or is expected to use, the product.  A product
306 | is a consumer product regardless of whether the product has substantial
307 | commercial, industrial or non-consumer uses, unless such uses represent
308 | the only significant mode of use of the product.
309 | 
310 |   "Installation Information" for a User Product means any methods,
311 | procedures, authorization keys, or other information required to install
312 | and execute modified versions of a covered work in that User Product from
313 | a modified version of its Corresponding Source.  The information must
314 | suffice to ensure that the continued functioning of the modified object
315 | code is in no case prevented or interfered with solely because
316 | modification has been made.
317 | 
318 |   If you convey an object code work under this section in, or with, or
319 | specifically for use in, a User Product, and the conveying occurs as
320 | part of a transaction in which the right of possession and use of the
321 | User Product is transferred to the recipient in perpetuity or for a
322 | fixed term (regardless of how the transaction is characterized), the
323 | Corresponding Source conveyed under this section must be accompanied
324 | by the Installation Information.  But this requirement does not apply
325 | if neither you nor any third party retains the ability to install
326 | modified object code on the User Product (for example, the work has
327 | been installed in ROM).
328 | 
329 |   The requirement to provide Installation Information does not include a
330 | requirement to continue to provide support service, warranty, or updates
331 | for a work that has been modified or installed by the recipient, or for
332 | the User Product in which it has been modified or installed.  Access to a
333 | network may be denied when the modification itself materially and
334 | adversely affects the operation of the network or violates the rules and
335 | protocols for communication across the network.
336 | 
337 |   Corresponding Source conveyed, and Installation Information provided,
338 | in accord with this section must be in a format that is publicly
339 | documented (and with an implementation available to the public in
340 | source code form), and must require no special password or key for
341 | unpacking, reading or copying.
342 | 
343 |   7. Additional Terms.
344 | 
345 |   "Additional permissions" are terms that supplement the terms of this
346 | License by making exceptions from one or more of its conditions.
347 | Additional permissions that are applicable to the entire Program shall
348 | be treated as though they were included in this License, to the extent
349 | that they are valid under applicable law.  If additional permissions
350 | apply only to part of the Program, that part may be used separately
351 | under those permissions, but the entire Program remains governed by
352 | this License without regard to the additional permissions.
353 | 
354 |   When you convey a copy of a covered work, you may at your option
355 | remove any additional permissions from that copy, or from any part of
356 | it.  (Additional permissions may be written to require their own
357 | removal in certain cases when you modify the work.)  You may place
358 | additional permissions on material, added by you to a covered work,
359 | for which you have or can give appropriate copyright permission.
360 | 
361 |   Notwithstanding any other provision of this License, for material you
362 | add to a covered work, you may (if authorized by the copyright holders of
363 | that material) supplement the terms of this License with terms:
364 | 
365 |     a) Disclaiming warranty or limiting liability differently from the
366 |     terms of sections 15 and 16 of this License; or
367 | 
368 |     b) Requiring preservation of specified reasonable legal notices or
369 |     author attributions in that material or in the Appropriate Legal
370 |     Notices displayed by works containing it; or
371 | 
372 |     c) Prohibiting misrepresentation of the origin of that material, or
373 |     requiring that modified versions of such material be marked in
374 |     reasonable ways as different from the original version; or
375 | 
376 |     d) Limiting the use for publicity purposes of names of licensors or
377 |     authors of the material; or
378 | 
379 |     e) Declining to grant rights under trademark law for use of some
380 |     trade names, trademarks, or service marks; or
381 | 
382 |     f) Requiring indemnification of licensors and authors of that
383 |     material by anyone who conveys the material (or modified versions of
384 |     it) with contractual assumptions of liability to the recipient, for
385 |     any liability that these contractual assumptions directly impose on
386 |     those licensors and authors.
387 | 
388 |   All other non-permissive additional terms are considered "further
389 | restrictions" within the meaning of section 10.  If the Program as you
390 | received it, or any part of it, contains a notice stating that it is
391 | governed by this License along with a term that is a further
392 | restriction, you may remove that term.  If a license document contains
393 | a further restriction but permits relicensing or conveying under this
394 | License, you may add to a covered work material governed by the terms
395 | of that license document, provided that the further restriction does
396 | not survive such relicensing or conveying.
397 | 
398 |   If you add terms to a covered work in accord with this section, you
399 | must place, in the relevant source files, a statement of the
400 | additional terms that apply to those files, or a notice indicating
401 | where to find the applicable terms.
402 | 
403 |   Additional terms, permissive or non-permissive, may be stated in the
404 | form of a separately written license, or stated as exceptions;
405 | the above requirements apply either way.
406 | 
407 |   8. Termination.
408 | 
409 |   You may not propagate or modify a covered work except as expressly
410 | provided under this License.  Any attempt otherwise to propagate or
411 | modify it is void, and will automatically terminate your rights under
412 | this License (including any patent licenses granted under the third
413 | paragraph of section 11).
414 | 
415 |   However, if you cease all violation of this License, then your
416 | license from a particular copyright holder is reinstated (a)
417 | provisionally, unless and until the copyright holder explicitly and
418 | finally terminates your license, and (b) permanently, if the copyright
419 | holder fails to notify you of the violation by some reasonable means
420 | prior to 60 days after the cessation.
421 | 
422 |   Moreover, your license from a particular copyright holder is
423 | reinstated permanently if the copyright holder notifies you of the
424 | violation by some reasonable means, this is the first time you have
425 | received notice of violation of this License (for any work) from that
426 | copyright holder, and you cure the violation prior to 30 days after
427 | your receipt of the notice.
428 | 
429 |   Termination of your rights under this section does not terminate the
430 | licenses of parties who have received copies or rights from you under
431 | this License.  If your rights have been terminated and not permanently
432 | reinstated, you do not qualify to receive new licenses for the same
433 | material under section 10.
434 | 
435 |   9. Acceptance Not Required for Having Copies.
436 | 
437 |   You are not required to accept this License in order to receive or
438 | run a copy of the Program.  Ancillary propagation of a covered work
439 | occurring solely as a consequence of using peer-to-peer transmission
440 | to receive a copy likewise does not require acceptance.  However,
441 | nothing other than this License grants you permission to propagate or
442 | modify any covered work.  These actions infringe copyright if you do
443 | not accept this License.  Therefore, by modifying or propagating a
444 | covered work, you indicate your acceptance of this License to do so.
445 | 
446 |   10. Automatic Licensing of Downstream Recipients.
447 | 
448 |   Each time you convey a covered work, the recipient automatically
449 | receives a license from the original licensors, to run, modify and
450 | propagate that work, subject to this License.  You are not responsible
451 | for enforcing compliance by third parties with this License.
452 | 
453 |   An "entity transaction" is a transaction transferring control of an
454 | organization, or substantially all assets of one, or subdividing an
455 | organization, or merging organizations.  If propagation of a covered
456 | work results from an entity transaction, each party to that
457 | transaction who receives a copy of the work also receives whatever
458 | licenses to the work the party's predecessor in interest had or could
459 | give under the previous paragraph, plus a right to possession of the
460 | Corresponding Source of the work from the predecessor in interest, if
461 | the predecessor has it or can get it with reasonable efforts.
462 | 
463 |   You may not impose any further restrictions on the exercise of the
464 | rights granted or affirmed under this License.  For example, you may
465 | not impose a license fee, royalty, or other charge for exercise of
466 | rights granted under this License, and you may not initiate litigation
467 | (including a cross-claim or counterclaim in a lawsuit) alleging that
468 | any patent claim is infringed by making, using, selling, offering for
469 | sale, or importing the Program or any portion of it.
470 | 
471 |   11. Patents.
472 | 
473 |   A "contributor" is a copyright holder who authorizes use under this
474 | License of the Program or a work on which the Program is based.  The
475 | work thus licensed is called the contributor's "contributor version".
476 | 
477 |   A contributor's "essential patent claims" are all patent claims
478 | owned or controlled by the contributor, whether already acquired or
479 | hereafter acquired, that would be infringed by some manner, permitted
480 | by this License, of making, using, or selling its contributor version,
481 | but do not include claims that would be infringed only as a
482 | consequence of further modification of the contributor version.  For
483 | purposes of this definition, "control" includes the right to grant
484 | patent sublicenses in a manner consistent with the requirements of
485 | this License.
486 | 
487 |   Each contributor grants you a non-exclusive, worldwide, royalty-free
488 | patent license under the contributor's essential patent claims, to
489 | make, use, sell, offer for sale, import and otherwise run, modify and
490 | propagate the contents of its contributor version.
491 | 
492 |   In the following three paragraphs, a "patent license" is any express
493 | agreement or commitment, however denominated, not to enforce a patent
494 | (such as an express permission to practice a patent or covenant not to
495 | sue for patent infringement).  To "grant" such a patent license to a
496 | party means to make such an agreement or commitment not to enforce a
497 | patent against the party.
498 | 
499 |   If you convey a covered work, knowingly relying on a patent license,
500 | and the Corresponding Source of the work is not available for anyone
501 | to copy, free of charge and under the terms of this License, through a
502 | publicly available network server or other readily accessible means,
503 | then you must either (1) cause the Corresponding Source to be so
504 | available, or (2) arrange to deprive yourself of the benefit of the
505 | patent license for this particular work, or (3) arrange, in a manner
506 | consistent with the requirements of this License, to extend the patent
507 | license to downstream recipients.  "Knowingly relying" means you have
508 | actual knowledge that, but for the patent license, your conveying the
509 | covered work in a country, or your recipient's use of the covered work
510 | in a country, would infringe one or more identifiable patents in that
511 | country that you have reason to believe are valid.
512 | 
513 |   If, pursuant to or in connection with a single transaction or
514 | arrangement, you convey, or propagate by procuring conveyance of, a
515 | covered work, and grant a patent license to some of the parties
516 | receiving the covered work authorizing them to use, propagate, modify
517 | or convey a specific copy of the covered work, then the patent license
518 | you grant is automatically extended to all recipients of the covered
519 | work and works based on it.
520 | 
521 |   A patent license is "discriminatory" if it does not include within
522 | the scope of its coverage, prohibits the exercise of, or is
523 | conditioned on the non-exercise of one or more of the rights that are
524 | specifically granted under this License.  You may not convey a covered
525 | work if you are a party to an arrangement with a third party that is
526 | in the business of distributing software, under which you make payment
527 | to the third party based on the extent of your activity of conveying
528 | the work, and under which the third party grants, to any of the
529 | parties who would receive the covered work from you, a discriminatory
530 | patent license (a) in connection with copies of the covered work
531 | conveyed by you (or copies made from those copies), or (b) primarily
532 | for and in connection with specific products or compilations that
533 | contain the covered work, unless you entered into that arrangement,
534 | or that patent license was granted, prior to 28 March 2007.
535 | 
536 |   Nothing in this License shall be construed as excluding or limiting
537 | any implied license or other defenses to infringement that may
538 | otherwise be available to you under applicable patent law.
539 | 
540 |   12. No Surrender of Others' Freedom.
541 | 
542 |   If conditions are imposed on you (whether by court order, agreement or
543 | otherwise) that contradict the conditions of this License, they do not
544 | excuse you from the conditions of this License.  If you cannot convey a
545 | covered work so as to satisfy simultaneously your obligations under this
546 | License and any other pertinent obligations, then as a consequence you may
547 | not convey it at all.  For example, if you agree to terms that obligate you
548 | to collect a royalty for further conveying from those to whom you convey
549 | the Program, the only way you could satisfy both those terms and this
550 | License would be to refrain entirely from conveying the Program.
551 | 
552 |   13. Use with the GNU Affero General Public License.
553 | 
554 |   Notwithstanding any other provision of this License, you have
555 | permission to link or combine any covered work with a work licensed
556 | under version 3 of the GNU Affero General Public License into a single
557 | combined work, and to convey the resulting work.  The terms of this
558 | License will continue to apply to the part which is the covered work,
559 | but the special requirements of the GNU Affero General Public License,
560 | section 13, concerning interaction through a network will apply to the
561 | combination as such.
562 | 
563 |   14. Revised Versions of this License.
564 | 
565 |   The Free Software Foundation may publish revised and/or new versions of
566 | the GNU General Public License from time to time.  Such new versions will
567 | be similar in spirit to the present version, but may differ in detail to
568 | address new problems or concerns.
569 | 
570 |   Each version is given a distinguishing version number.  If the
571 | Program specifies that a certain numbered version of the GNU General
572 | Public License "or any later version" applies to it, you have the
573 | option of following the terms and conditions either of that numbered
574 | version or of any later version published by the Free Software
575 | Foundation.  If the Program does not specify a version number of the
576 | GNU General Public License, you may choose any version ever published
577 | by the Free Software Foundation.
578 | 
579 |   If the Program specifies that a proxy can decide which future
580 | versions of the GNU General Public License can be used, that proxy's
581 | public statement of acceptance of a version permanently authorizes you
582 | to choose that version for the Program.
583 | 
584 |   Later license versions may give you additional or different
585 | permissions.  However, no additional obligations are imposed on any
586 | author or copyright holder as a result of your choosing to follow a
587 | later version.
588 | 
589 |   15. Disclaimer of Warranty.
590 | 
591 |   THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
592 | APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
596 | PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
597 | IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
599 | 
600 |   16. Limitation of Liability.
601 | 
602 |   IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
610 | SUCH DAMAGES.
611 | 
612 |   17. Interpretation of Sections 15 and 16.
613 | 
614 |   If the disclaimer of warranty and limitation of liability provided
615 | above cannot be given local legal effect according to their terms,
616 | reviewing courts shall apply local law that most closely approximates
617 | an absolute waiver of all civil liability in connection with the
618 | Program, unless a warranty or assumption of liability accompanies a
619 | copy of the Program in return for a fee.
620 | 
621 |                      END OF TERMS AND CONDITIONS
622 | 
623 |             How to Apply These Terms to Your New Programs
624 | 
625 |   If you develop a new program, and you want it to be of the greatest
626 | possible use to the public, the best way to achieve this is to make it
627 | free software which everyone can redistribute and change under these terms.
628 | 
629 |   To do so, attach the following notices to the program.  It is safest
630 | to attach them to the start of each source file to most effectively
631 | state the exclusion of warranty; and each file should have at least
632 | the "copyright" line and a pointer to where the full notice is found.
633 | 
634 |     <one line to give the program's name and a brief idea of what it does.>
635 |     Copyright (C) <year>  <name of author>
636 | 
637 |     This program is free software: you can redistribute it and/or modify
638 |     it under the terms of the GNU General Public License as published by
639 |     the Free Software Foundation, either version 3 of the License, or
640 |     (at your option) any later version.
641 | 
642 |     This program is distributed in the hope that it will be useful,
643 |     but WITHOUT ANY WARRANTY; without even the implied warranty of
644 |     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
645 |     GNU General Public License for more details.
646 | 
647 |     You should have received a copy of the GNU General Public License
648 |     along with this program.  If not, see <https://www.gnu.org/licenses/>.
649 | 
650 | Also add information on how to contact you by electronic and paper mail.
651 | 
652 |   If the program does terminal interaction, make it output a short
653 | notice like this when it starts in an interactive mode:
654 | 
655 |     <program>  Copyright (C) <year>  <name of author>
656 |     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
657 |     This is free software, and you are welcome to redistribute it
658 |     under certain conditions; type `show c' for details.
659 | 
660 | The hypothetical commands `show w' and `show c' should show the appropriate
661 | parts of the General Public License.  Of course, your program's commands
662 | might be different; for a GUI interface, you would use an "about box".
663 | 
664 |   You should also get your employer (if you work as a programmer) or school,
665 | if any, to sign a "copyright disclaimer" for the program, if necessary.
666 | For more information on this, and how to apply and follow the GNU GPL, see
667 | <https://www.gnu.org/licenses/>.
668 | 
669 |   The GNU General Public License does not permit incorporating your program
670 | into proprietary programs.  If your program is a subroutine library, you
671 | may consider it more useful to permit linking proprietary applications with
672 | the library.  If this is what you want to do, use the GNU Lesser General
673 | Public License instead of this License.  But first, please read
674 | <https://www.gnu.org/licenses/why-not-lgpl.html>.
675 | 


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