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copied!<p>How you detect EOF depends on what you're using to read the stream:</p> <pre><code>function result on EOF or error -------- ---------------------- fgets() NULL fscanf() number of succesful conversions less than expected fgetc() EOF fread() number of elements read less than expected </code></pre> <p>Check the result of the input call for the appropriate condition above, then call <code>feof()</code> to determine if the result was due to hitting EOF or some other error. </p> <p>Using <code>fgets()</code>:</p> <pre><code> char buffer[BUFFER_SIZE]; while (fgets(buffer, sizeof buffer, stream) != NULL) { // process buffer } if (feof(stream)) { // hit end of file } else { // some other error interrupted the read } </code></pre> <p>Using <code>fscanf()</code>:</p> <pre><code>char buffer[BUFFER_SIZE]; while (fscanf(stream, "%s", buffer) == 1) // expect 1 successful conversion { // process buffer } if (feof(stream)) { // hit end of file } else { // some other error interrupted the read } </code></pre> <p>Using <code>fgetc()</code>:</p> <pre><code>int c; while ((c = fgetc(stream)) != EOF) { // process c } if (feof(stream)) { // hit end of file } else { // some other error interrupted the read } </code></pre> <p>Using <code>fread()</code>:</p> <pre><code>char buffer[BUFFER_SIZE]; while (fread(buffer, sizeof buffer, 1, stream) == 1) // expecting 1 // element of size // BUFFER_SIZE { // process buffer } if (feof(stream)) { // hit end of file } else { // some other error interrupted read } </code></pre> <p>Note that the form is the same for all of them: check the result of the read operation; if it failed, <em>then</em> check for EOF. You'll see a lot of examples like:</p> <pre><code>while(!feof(stream)) { fscanf(stream, "%s", buffer); ... } </code></pre> <p>This form doesn't work the way people think it does, because <code>feof()</code> won't return true until <em>after</em> you've attempted to read past the end of the file. As a result, the loop executes one time too many, which may or may not cause you some grief. </p>

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