feof() in C file handling

c file-handling feof
sud03r picture sud03r · Apr 14, 2010 · Viewed 7.1k times · Source

I am reading a binary file byte-by-byte,i need determine that whether or not eof has reached.

feof() doesn't works as "eof is set only when a read request for non-existent byte is made". So, I can have my custom check_eof like:

if ( fread(&byte,sizeof(byte),1,fp) != 1) {
    if(feof(fp))
    return true;
}
return false;

But the problem is, in case when eof is not reached, my file pointer is moved a byte ahead. So a solution might be to use ftell() and then fseek() to get it to correct position.

Another solution might be to buffer the byte ahead in some temporary storage.

Any better solutions?

Answer

jamesdlin picture jamesdlin · Apr 14, 2010

If you're reading a byte at a time, the idiomatic way to do this is with fgetc:

int c;
while ((c = fgetc(fp)) != EOF) {
   // Do something.
}

and then you shouldn't need to deal with feof.

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