Yes,I think I have read some of them about audio part,I didn't find anything about this function.
And the API document does not give any example how to use this.
Just some useless parameter shown same as Visual Studio tip does.
https://www.sfml-dev.org/documentation/2.5.1/classsf_1_1Music.php#ae7b339f0a957dfad045f3f28083a015eAnd I have tried google,no example.
So I hope to get some example here.
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OK, never mind.I was stupid.I thought sf::Time shoud use like sf::Time(1.807) or something like this.
Turns out it is sf::seconds(1.807) which is sf::Time type.
Not what I was expected this is working this way.