std::basic_ofstream<CharT,Traits>:: is_open
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          std::basic_ofstream
         
        
        
         
          
           
            
          
          
          
         
        
       
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                   basic_ofstream::is_open
                  
                 
                
                
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             bool
            
            is_open
            
             (
            
            
             )
            
            
             const
            
            
             ;
            
           
           
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         ||
Checks if the file stream has an associated file.
Effectively calls rdbuf()->is_open() .
Parameters
(none)
Return value
true if the file stream has an associated file, false otherwise.
Example
| 
         This section is incomplete
          Reason: no example  | 
       
Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior | 
|---|---|---|---|
| LWG 365 | C++98 | 
         
          is_open
         
         was not declared with
         
          
           const
          
         
         qualifier
         | 
        declared with const qualifier | 
See also
| 
         opens a file and associates it with the stream
          (public member function)  | 
       |
| 
         closes the associated file
          (public member function)  | 
       
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