How to copy IPAddress class into character buffer? Getting error: "inet_ntop' was not declared in this scope"

Question

I am using the WiFi library and trying to store the IP address in a character buffer so that I can print it out to an lcd that only accepts character buffers. My code for doing this:

 char * IPAD = new char[40
 IPAddress ip = WiFi.localIP();
 Serial.println(ip);
 char * bufIP = new char[40]();
 sprintf(bufIP, "%s", inet_ntop(ip));
 lcd.string(ip);

But when I compile this I get the error:

"inet_ntop' was not declared in this scope"

Help?

• Juraj: try lcd.print(ip); lcd libraries use to implement Print and IPAddress implements Printable
• garson: My LCD library only accepts char* elements :(
• Juraj: then use numbers ip[0], ip[1], ip[2], ip[3]
• Craig: Which arduino are you using?

Answer 1

An IPAddress is a class. You can't use it like a number (although in certain circumstances you can assign it to a uint32_t and it gives you the numeric representation).

Also, the inet_* functions are only really relevant on a POSIX system with a full network stack - i.e., a computer, not a little Arduino without a proper networking stack.

You can, though, easily access the individual bytes of the IP address through the [] operator and place them into a char array with the right format:

sprintf(bufIP, "%d.%d.%d.%d", ip[0], ip[1], ip[2], ip[3]);

Answer 2

char IP[] = "000.000.000.000";
WiFi.localIP().toString().toCharArray(IP, 16);
Serial.printf("Local IP Address: %s", IP);

• Rohit Gupta: Please explain how it works.