std::ios_base::openmode
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                    |   typedef /*implementation defined*/ openmode;  | 
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|   static constexpr openmode app = /*implementation defined*/ static constexpr openmode binary = /*implementation defined*/  | 
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Specifies available file open flags. It is a bitmask type, the following constants are defined:
| Constant | Explanation | 
| app | seek to the end of stream before each write | 
| binary | open in binary mode | 
| in | open for reading | 
| out | open for writing | 
| trunc | discard the contents of the stream when opening | 
| ate | seek to the end of stream immediately after open | 
[edit] Example
| This section is incomplete Reason: no example  |