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From: sln on 9 Feb 2010 20:29
On Tue, 9 Feb 2010 11:16:30 -0800 (PST), "freesoft12(a)gmail.com" <freesoft12(a)gmail.com> wrote:

>Hi,
>
>I have a written a C++ program that writes a set of paths into a
>binary file. In the program, the 'write_binary()', writes to the
>binary file and the 'read_binary()' opens the binary file, reads the
>data and prints it out.
>
[your code snipped]

It looks like you are dealing with strings and is a simple case of
writing the length and string combo's.

If thats all your doing, the solution is to mitigate machine dependencies.
There's really no need to travel down the *binary* highway unless you have to.
The Perl itself couldn't be simpler, its almost a one liner.

-sln

-----------------------------

// JBin.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <string>
#include <vector>

using namespace std;

void write_binary();
void read_binary();

int _tmain(int argc, _TCHAR* argv[])
{
write_binary();
read_binary();
system("perl ../jbin.pl");
return 0;
}

//
void write_binary()
{
vector<string> v;
v.push_back( "/a/b/c/d");
v.push_back( "/e/f");
v.push_back( "../h");

FILE *fp = fopen( "rw_binary.dat", "w"); // wb ??
if (!fp)
{
printf( "Error: Unable to open ./rw_binary.dat for write\n");
exit(1);
}
char buf[100];
for( vector<string>::const_iterator it(v.begin()),itEnd(v.end()); it!=itEnd; it++)
{
strcat( itoa( it->size(), buf, 10), "\n");
fputs( buf, fp);
fputs( it->c_str(), fp);
}
fclose(fp);
}

//
void read_binary()
{
FILE *fp = fopen( "rw_binary.dat", "r"); // rb ??
if (!fp)
{
printf( "Error: Unable to open ./rw_binary.dat for read\n");
exit(1);
}
printf( "\nFrom C++ ...\n");
char buf[100];
while (!feof(fp) && fgets( buf, 100, fp))
{
size_t count = atoi( buf);
char *sdata = (char *)malloc( count+1);
memset( sdata, 0, count+1);
fread( sdata, count, 1, fp);
printf( "'%s'\n", sdata);
free( sdata);
}
fclose(fp);
}

/*
# Jbin.pl
use strict;
use warnings;

open (my $fh, '<', 'rw_binary.dat') or die "Cannot open 'rw_binary.dat' for read: $!";
print "\nFrom perl ...\n";

my $buf;
while (<$fh>) {
read ($fh, $buf, $_);
print "'$buf'\n";
}
close($fh);
__END__
*/

/* Console output:

From C++ ...
'/a/b/c/d'
'/e/f'
'../h'

From perl ...
'/a/b/c/d'
'/e/f'
'../h'
Press any key to continue . . .
*/


From: Peter Makholm on 10 Feb 2010 02:03
"freesoft12(a)gmail.com" <freesoft12(a)gmail.com> writes:

> Sorry about that, I posted the Perl program that I was playing with.
> Here is the orig Perl program:

Many of the comments made by Peter J. Holzer and me still apply.

//Makholm
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