How to get the size of an array of type char? [duplicate]

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• size of array passed to C++ function? [duplicate] 7 answers

I have a problem when acquiring the size of an array of type char, I pass an array of type char to a function and in the function I want to get the size, but I can't get the correct one.

void dato(char data[]);
int main (){
char datos[6];
dato(datos);
}
void dato(char data[]){
int Long_data = sizeof(data) / sizeof(data[0]);
printf("long data = %i\n", Long_data);
}

I expect the output of long_data to be 6, but the actual output is 4.