[[NoV]LaZ]

IsPlayerInAnyVehicle has only one parameter, which is playerid, also it is used to check if a player is in a vehicle (any).
https://sampwiki.blast.hk/wiki/IsPlayerInAnyVehicle

pawn Код:

if(!strcmp(cmd, "/nos", true))
{
    if(!IsPlayerAdmin(playerid)) return SendClientMessage(playerid, COLOR_RED, "You aren't admin!");
    else if(!IsPlayerInAnyVehicle(playerid)) return SendClientMessage(playerid, COLOR_RED, "You have to be in a vehicle");
    else if(IsPlayerInInvalidNosVehicle(playerid)) return SendClientMessage(playerid, COLOR_ORANGE, "NOS can't be added on this vehicle!");
    {
        AddVehicleComponent(GetPlayerVehicleID(playerid), 1010);
        GivePlayerMoney(playerid, -2500);
        PlayerPlaySound(playerid, 1133, 0.0, 0.0, 0.0);
        return 1;
    }
}