[[XST]O_x]

pawn Code:

new count = 0,
    string[64],
    name[24];

public OnPlayerConnect(playerid)
{
    count++;
    GetPlayerName(playerid,name,24);
    format(string,sizeof(string),"%s has joined! He is player number %d",name,count);
    SendClientMessageToAll(-1,string);
    return 1;
}
public OnPlayerDisconnect(playerid)
{
    count--;
    return 1;
}