[Konstantinos]

Not sure how you want it, but an example!

pawn Код:

CMD:cuff(playerid, params[])
{
    new
        id,
        id2
    ;
    if(sscanf(params, "uu", id, id2)) return SendClientMessage(playerid, -1, "Usage: /cuff <playerid1> <playerid2>");
    if(id == INVALID_PLAYER_ID) return SendClientMessage(playerid, -1, "Player A is not connected");
    if(id2 == INVALID_PLAYER_ID) return SendClientMessage(playerid, -1, "Player B is not connected");
    new
        Float: pos[ 3 ]
    ;
    GetPlayerPos(id2, pos[ 0 ], pos[ 1 ], pos[ 2 ]);
    if(IsPlayerInRangeOfPoint(id, 5.0, pos[ 0 ], pos[ 1 ], pos[ 2 ])) 
    SendClientMessage(playerid, -1, "Player A is in range of player B!");
    return 1;
}