鸵鸟流和结束 [英] ostringstream and ends

问题描述

我一直在和别人的代码一起工作，注意到在所有使用ostringsteam的时候，他们习惯于显式地添加 std :: ends 。

I've been working with somebody else's code and noticed that on all uses of ostringsteam they are in the habit of explicitly appending std::ends.

这是我从来没有做过的，从来没有遇到过问题。

This is something I've never done and have never encountered a problem.

它不会出现， std :: ends 在以下代码中有什么区别？

It doesn't appear to, but should std::ends make any difference in the following code?

ostringstream message;
message << "Hello world, version " << 2 /* << std::ends ??? */;
printf( "%s\n", message.str().c_str() );

推荐答案

附加 std :: ends 的的 会返回一个以null结尾的 char * 。同样的不是（现已过时） strstream s的情况，其中追加 std :: ends 是必要的。我相信作者根本不知道这种改变的行为。

Appending std::ends is nonsense here since stringstream’s c_str returns a null-terminated char*. The same was not the case for the (now deprecated) strstreams where appending std::ends was necessary. I believe the author simply didn’t know of this changed behaviour.

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