I am having a tough time trying to get a simple C++ program to behave correctly in a Fedora 9 emulated environment under Parallels Desktop (v4.0.3810) running on a Macbook (2.4 GHz Intel Core 2 Duo). Basically, seeking to the end of a file being written is not working right. The code that I use (called junk.C) is listed below:
And to compile and run:
The erroneous value is shown in bold. It should have resulted in 32, not 0. It's as if the seek direction flag is being ignored by iostream::seekp() when run on the emulated Fedora system. When run on a native i386 machine (old Compaq from 2002) with an IDENTICAL Fedora Core OS installed, the code runs correctly. Furthermore, when I md5sum the compiled codes on the Compaq and under the emulated system, the executables are identical. And finally, even when I include the -static option to force static linking, the resulting executables also have identical checksums:
These were all compiled with the v4.3.0 gcc that comes standard with Fedora Core 9:
Can anyone suggest something I might be missing? Some hidden DLL or plugin causing the difference in behavior? Just one more data point: the above code compiles and executes correctly under the OS X g++ compiler. Thanks.
#include <fstream>
#include <iostream>
int main()
{
std::fstream outFile("junk.txt", std::ios:ut | std::ios::binary);
char msg[32];
for (int i=0; i<32; i++)
msg = i;
outFile.write(msg, 32);
#include <iostream>
int main()
{
std::fstream outFile("junk.txt", std::ios:
char msg[32];
for (int i=0; i<32; i++)
msg = i;
outFile.write(msg, 32);
outFile.flush();
std::cout << "After writing 32 chars: " << std::endl;
std::cout << "tellp = " << outFile.tellp() << std::endl;
outFile.seekp(0, std::ios::beg);
std::cout << "After seeking to beginning:" << std::endl;
std::cout << "tellp = " << outFile.tellp() << std::endl;
// Here's the one that fails under Parallels Fedora Core
outFile.seekp(0, std::ios::end);
std::cout << "After seeking to end:" << std::endl;
std::cout << "tellp = " << outFile.tellp() << std::endl;
outFile.seekp(16, std::ios::beg);
std::cout << "After seeking 16 from beginning:" << std::endl;
std::cout << "tellp = " << outFile.tellp() << std::endl;
return 0;
}
And to compile and run:
The erroneous value is shown in bold. It should have resulted in 32, not 0. It's as if the seek direction flag is being ignored by iostream::seekp() when run on the emulated Fedora system. When run on a native i386 machine (old Compaq from 2002) with an IDENTICAL Fedora Core OS installed, the code runs correctly. Furthermore, when I md5sum the compiled codes on the Compaq and under the emulated system, the executables are identical. And finally, even when I include the -static option to force static linking, the resulting executables also have identical checksums:
These were all compiled with the v4.3.0 gcc that comes standard with Fedora Core 9:
Can anyone suggest something I might be missing? Some hidden DLL or plugin causing the difference in behavior? Just one more data point: the above code compiles and executes correctly under the OS X g++ compiler. Thanks.
