官网的解释:http://www.dukascopy.com/wiki/index.php/Close_Order
The unconditional close order is sent to the marketplace server and routed to the liquidity source having the best available price at that time. The order at this point may be executed in full, executed partially, or rejected. The reason for rejection would be that the price at this time was no longer satisfying the embedded conditions when the market order was sent. Remember that unconditional does not mean that the close order will be executed at any price condition.
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