Re: Problem with file handling

From:

Victor Bazarov <v.bazarov@comcast.invalid>

Newsgroups:

comp.lang.c++

Date:

Mon, 27 Sep 2010 16:10:49 -0400

Message-ID:

<i7qto9$utg$1@news.eternal-september.org>

On 9/27/2010 4:02 PM, Jorgen Grahn wrote:

On Mon, 2010-09-27, Victor Bazarov wrote:

On 9/27/2010 10:24 AM, bintom wrote:

I'm having a problem with file handling.

In main(), I have written to 2 binary files -

ABC.TXT, which contains records of type employee in ascending order of
empid and;
XYZ.TXT, which also contains records of type employee, but in
descending order of empid.

If the files are binary, and you call them FOO.TXT, your
users will be angry ...

I am trying to write all the records in the 2 files, into a 3rd file
NEW.TXT, in ascending order. My program is given below. It writes
correctly to the 1st 2 files but does not do the combined write.

Any help will be appreciated.

I would use a different approach. Load both files each in its own
vector, sort them, then use 'std::merge' to get the resulting vector,
then dump the vector in the third file.

That would scale badly to gigabytes of records though. I'm guessing
that's not the intent of the the exercise.

Gigabytes of records? Of *employees*? Really? :-)

(Not that I find the exercise very useful as it is. I've never seen a
record-based file format like this one where it pays off to seek -- if
you want that kind of thing you use a simple database, or keep your
source files sorted ascending ...)

V
--
I do not respond to top-posted replies, please don't ask