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| <h3 class="section">12.1 Streams</h3> |
| |
| <p>For historical reasons, the type of the C data structure that represents |
| a stream is called <code>FILE</code> rather than “stream”. Since most of |
| the library functions deal with objects of type <code>FILE *</code>, sometimes |
| the term <dfn>file pointer</dfn> is also used to mean “stream”. This leads |
| to unfortunate confusion over terminology in many books on C. This |
| manual, however, is careful to use the terms “file” and “stream” |
| only in the technical sense. |
| <a name="index-file-pointer-915"></a> |
| <a name="index-stdio_002eh-916"></a>The <code>FILE</code> type is declared in the header file <samp><span class="file">stdio.h</span></samp>. |
| |
| <!-- stdio.h --> |
| <!-- ISO --> |
| <div class="defun"> |
| — Data Type: <b>FILE</b><var><a name="index-FILE-917"></a></var><br> |
| <blockquote><p>This is the data type used to represent stream objects. A <code>FILE</code> |
| object holds all of the internal state information about the connection |
| to the associated file, including such things as the file position |
| indicator and buffering information. Each stream also has error and |
| end-of-file status indicators that can be tested with the <code>ferror</code> |
| and <code>feof</code> functions; see <a href="EOF-and-Errors.html#EOF-and-Errors">EOF and Errors</a>. |
| </p></blockquote></div> |
| |
| <p><code>FILE</code> objects are allocated and managed internally by the |
| input/output library functions. Don't try to create your own objects of |
| type <code>FILE</code>; let the library do it. Your programs should |
| deal only with pointers to these objects (that is, <code>FILE *</code> values) |
| rather than the objects themselves. |
| <!-- !!! should say that FILE's have "No user-serviceable parts inside." --> |
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