[PrivatioBoni]

I could be wrong, but try this:

Код:

new ip[16];
GetPlayerIp(playerid, ip, sizeof(ip));

if (!strcmp([variable for person's IP], ip, true))
{
	//auto login code here
}

Example of "Variable for person's IP":

Код:

new ip[16];
GetPlayerIp(playerid, ip, sizeof(ip));

if (!strcmp(PlayerInfo[playerid][pIPAddress], ip, true))
{
	//auto login code here
}

Also, just noticed this (very recent!) thread exists, which may be useful: https://sampforum.blast.hk/showthread.php?tid=589891