devdocs/c/io%2Ffeof.html


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    <h1 id="firstHeading" class="firstHeading">feof</h1>            <table class="t-dcl-begin"> <tr class="t-dsc-header"> <th> Defined in header <code>&lt;stdio.h&gt;</code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl"> <td class="t-dcl-nopad"> <pre data-language="c">int feof( FILE *stream );</pre>
</td> <td class="t-dcl-nopad"> </td> <td class="t-dcl-nopad"> </td> </tr>  </table> <p>Checks if the end of the given file stream has been reached.</p>
<h3 id="Parameters"> Parameters</h3> <table class="t-par-begin"> <tr class="t-par"> <td> stream </td> <td> - </td> <td> the file stream to check </td>
</tr>
</table> <h3 id="Return_value"> Return value</h3> <p>nonzero value if the end of the stream has been reached, otherwise <code>0</code></p>
<h3 id="Notes"> Notes</h3> <p>This function only reports the stream state as reported by the most recent I/O operation, it does not examine the associated data source. For example, if the most recent I/O was a <code><a href="fgetc" title="c/io/fgetc">fgetc</a></code>, which returned the last byte of a file, <code>feof</code> returns zero. The next <code><a href="fgetc" title="c/io/fgetc">fgetc</a></code> fails and changes the stream state to <i>end-of-file</i>. Only then <code>feof</code> returns non-zero.</p>
<p>In typical usage, input stream processing stops on any error; <code>feof</code> and <code><a href="ferror" title="c/io/ferror">ferror</a></code> are then used to distinguish between different error conditions.</p>
<h3 id="Example"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include &lt;stdio.h&gt;
#include &lt;stdlib.h&gt;
 
int main(void)
{
    const char* fname = "/tmp/unique_name.txt"; // or tmpnam(NULL);
    int is_ok = EXIT_FAILURE;
 
    FILE* fp = fopen(fname, "w+");
    if (!fp) {
        perror("File opening failed");
        return is_ok;
    }
    fputs("Hello, world!\n", fp);
    rewind(fp);
 
    int c; // note: int, not char, required to handle EOF
    while ((c = fgetc(fp)) != EOF) // standard C I/O file reading loop
        putchar(c);
 
    if (ferror(fp))
        puts("I/O error when reading");
    else if (feof(fp)) {
        puts("End of file is reached successfully");
        is_ok = EXIT_SUCCESS;
    }
 
    fclose(fp);
    remove(fname);
    return is_ok;
}</pre></div> <p>Possible output:</p>
<div class="text source-text"><pre data-language="c">Hello, world!
End of file is reached successfully</pre></div> </div> <h3 id="References"> References</h3>  <ul>
<li> C11 standard (ISO/IEC 9899:2011): </li>
<ul><li> 7.21.10.2 The feof function (p: 339) </li></ul>
<li> C99 standard (ISO/IEC 9899:1999): </li>
<ul><li> 7.19.10.2 The feof function (p: 305) </li></ul>
<li> C89/C90 standard (ISO/IEC 9899:1990): </li>
<ul><li> 4.9.10.2 The feof function </li></ul>
</ul>         <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="clearerr" title="c/io/clearerr"> <span class="t-lines"><span>clearerr</span></span></a></div> </td> <td> clears errors <br> <span class="t-mark">(function)</span>  </td>
</tr> <tr class="t-dsc"> <td> <div><a href="perror" title="c/io/perror"> <span class="t-lines"><span>perror</span></span></a></div> </td> <td> displays a character string corresponding of the current error to <code><a href="std_streams" title="c/io/std streams">stderr</a></code> <br> <span class="t-mark">(function)</span>  </td>
</tr> <tr class="t-dsc"> <td> <div><a href="ferror" title="c/io/ferror"> <span class="t-lines"><span>ferror</span></span></a></div> </td> <td> checks for a file error <br> <span class="t-mark">(function)</span>  </td>
</tr> <tr class="t-dsc"> <td colspan="2"> <span><a href="https://en.cppreference.com/w/cpp/io/c/feof" title="cpp/io/c/feof">C++ documentation</a></span> for <code>feof</code> </td>
</tr> </table>            <div class="_attribution">
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