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[QUOTE="Beej Jorgensen, post: 3910485"]
Some will likely try to redirect you to a C++ newsgroup, but this is
actually a C problem, IMO.

I'm going to bet that you've assumed that feof() will return true as
soon as you've read up through the last byte of the file.  But this is
incorrect; feof() is set once you've read /past/ the end of the file.
[Though I'm having trouble finding the bits of the standard that spell
it out quite so explicitly.]

This is a good time to do some desk checking.  Let's say your file has
just one struct in it, so it should print out one struct, right?.  Trace
through this one step at a time.

1. EOF?  No.

2. Read a record (struct #1)
   (EOF remains clear at this time because you haven't yet read _past_
   the end of the file--you've only read up to the end.)

3. Print a record (struct #1) <<<<<<<<<<<<<<

4. EOF?  No.

5. Read a record (fails, returning 0, because you read off the end)
   (You should check the return value of fread() to make sure it has
   read the number of items you think it has.  In any case, at this
   point the EOF flag is set because you've read past the end of the
   file.)

6. Print a record (struct #1, again) <<<<<<<<<<<<<<

7. EOF?  Yes

So notice that we've printed a record twice even though it's the only
record in the file.

What you want to do is not print those values again if feof() is true.
A couple of relatively clean ways I've seen to do this are:

// using the comma operator, read a record, then, for the while()
    // condition, check the status of feof()

while(fread(&teu,sizeof(ender),1,fp), !feof(fp)) {
        cout<<teu.rua<<"\n";
        cout<<teu.n<<"\n";
    }

or, perhaps more clearly:

// print records while fread() returns more than zero items
    // (in this case you only asked for 1 item, so it should always
    // return either 0 or 1 items.)

while(fread(&teu,sizeof(ender),1,fp) > 0) {
        cout<<teu.rua<<"\n";
        cout<<teu.n<<"\n";
    }

You can also test for more errors by clearing the error flag before the
while() loop with clearerr(), and then testing with ferror() after the
while loop.  (Or, in the first case, by adding &&!ferror() to the while
condition.)

-Beej
[/QUOTE]

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