Unknown type name 'IRsend'

Question

In the C file in simplesample_mqtt.c, which connects Arduino to the Azure IoT hub, I need to use the IRsend and IrRemoteESP8266 libraries to send an infrared signal with Azure IoT hub.

1. #include <IRremoteESP8266.h>
2. #include <IRsend.h>
3. IRsend irsend(10); // An IR LED is controlled by GPIO pin 4 (D2)

I don't have any problem when I use this code in my main Ardunio file. But when I use these includes in a C file (implesample_mqtt.c), I get this error from line 3: "unknown type name 'IRsend'".

error full info : Arduino: 1.8.2 (Windows 10), Board: "NodeMCU 0.9 (ESP-12 Module), 80 MHz, 115200, 4M (3M SPIFFS)"

In file included from sketch\simplesample_mqtt.c:29:0:

C:\Program Files (x86)\Arduino\libraries\IRremoteESP8266\src/IRsend.h:29:1: error: unknown type name 'class'

class IRsend {

C:\Program Files (x86)\Arduino\libraries\IRremoteESP8266\src/IRsend.h:29:14: error: expected '=', ',', ';', 'asm' or 'attribute' before '{' token

class IRsend {

simplesample_mqtt.c:31: error: unknown type name 'IRsend'

IRsend irsend(10); // An IR LED is controlled by GPIO pin 4 (D2)

simplesample_mqtt.c:31: error: expected declaration specifiers or '...' before numeric constant

IRsend irsend(10); // An IR LED is controlled by GPIO pin 4 (D2)

exit status 1 unknown type name 'IRsend'

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Answer 1

I solved this problem. The reason for this is because main ardunio is c++ and simplesample_mqtt.c is c code and we have to use c++ code in c code :

i main ardunio file you have to declare function like this :

extern "C" void TurnOn();
void TurnOn()
{
    digitalWrite(RELAY_SONOFF, HIGH);     
    digitalWrite(LED_SONOFF, HIGH);
}

and use this function in c code :

void TurnOn();
EXECUTE_COMMAND_RESULT TurnOn(ContosoAnemometer* device)
{
    (void)device;
    TurnOn();
    (void)printf("Turning fan on.\r\n");
    return EXECUTE_COMMAND_SUCCESS;
}