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### 158. Underspecified semantics for `setbuf()`

Section: 31.6.3.5.2 [streambuf.virt.buffer] Status: TC1 Submitter: Dietmar Kühl Opened: 1999-07-20 Last modified: 2016-01-28

Priority: Not Prioritized

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Discussion:

The default behavior of `setbuf()` is described only for the situation that `gptr() != 0 && gptr() != egptr()`: namely to do nothing. What has to be done in other situations is not described although there is actually only one reasonable approach, namely to do nothing, too.

Since changing the buffer would almost certainly mess up most buffer management of derived classes unless these classes do it themselves, the default behavior of `setbuf()` should always be to do nothing.

Proposed resolution:

Change 31.6.3.5.2 [streambuf.virt.buffer], paragraph 3, Default behavior, to: "Default behavior: Does nothing. Returns this."