function
<cstdio>
feof
int feof ( FILE * stream );
Check end-of-file indicator
Checks whether the end-of-File indicator associated with stream is set, returning a value different from zero if it is.
This indicator is generally set by a previous operation on the stream that attempted to read at or past the end-of-file.
Notice that stream's internal position indicator may point to the end-of-file for the next operation, but still, the end-of-file indicator may not be set until an operation attempts to read at that point.
This indicator is cleared by a call to clearerr, rewind, fseek, fsetpos or freopen. Although if the position indicator is not repositioned by such a call, the next i/o operation is likely to set the indicator again.
Parameters
- stream
- Pointer to a FILE object that identifies the stream.
Return Value
A non-zero value is returned in the case that the end-of-file indicator associated with the stream is set.
Otherwise, zero is returned.
Example
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/* feof example: byte counter */
#include <stdio.h>
int main ()
{
FILE * pFile;
int n = 0;
pFile = fopen ("myfile.txt","rb");
if (pFile==NULL) perror ("Error opening file");
else
{
while (fgetc(pFile) != EOF) {
++n;
}
if (feof(pFile)) {
puts ("End-of-File reached.");
printf ("Total number of bytes read: %d\n", n);
}
else puts ("End-of-File was not reached.");
fclose (pFile);
}
return 0;
}
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This code opens the file called myfile.txt, and counts the number of characters that it contains by reading all of them one by one. The program checks whether the end-of-file was reached, and if so, prints the total number of bytes read.
See also
- clearerr
- Clear error indicators (function)
- ferror
- Check error indicator (function)