serialize to a file using FileOutputStream

[Paul Yang]

Hi,
I am new to protocol buffers, and I am trying to serialize a message
to a file. I need to serialize the file so that in can be opened in
Java using parseDelimitedFrom(). However, when I write to the file
using SerializeToCodedStream or SerializeWithCachedSizes, nothing
happens to the serializedMessage.bin file, and it stays at 0 bytes.
Why is nothing being written to the file? I have attached the code
below:

int fd = open("serializedMessage.bin", O_WRONLY);

google::protobuf::io::ZeroCopyOutputStream* fileOutput = new
google::protobuf::io::FileOutputStream(fd);

google::protobuf::io::CodedOutputStream* codedOutput = new
google::protobuf::io::CodedOutputStream(fileOutput);

codedOutput->WriteVarint32(message1.ByteSize());
message1.SerializeToCodedStream(codedOutput);
// also tried snap1.SerializeWithCachedSizes(codedOutput)

close(fd);

Thanks!

[Daniel Wright]

I think it's being buffered in the FileOutputStream -- you should be sure to delete the output streams (in the reverse order that you created them) before you close the file.

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[Paul Yang]

thanks! I tried that and it works now!

On Oct 11, 4:03 pm, Daniel Wright <dwri...@google.com> wrote:
> I think it's being buffered in the FileOutputStream -- you should be sure to
> delete the output streams (in the reverse order that you created them)
> before you close the file.
>

> On Mon, Oct 11, 2010 at 1:07 PM, Paul Yang <mjpabl...@gmail.com> wrote:
> > Hi,
> > I am new to protocol buffers, and I am trying to serialize a message
> > to a file.  I need to serialize the file so that in can be opened in
> > Java using parseDelimitedFrom().  However, when I write to the file
> > using SerializeToCodedStream or SerializeWithCachedSizes, nothing
> > happens to the serializedMessage.bin file, and it stays at 0 bytes.
> > Why is nothing being written to the file?  I have attached the code
> > below:
>
> > int fd = open("serializedMessage.bin", O_WRONLY);
>
> > google::protobuf::io::ZeroCopyOutputStream* fileOutput = new
> > google::protobuf::io::FileOutputStream(fd);
>
> > google::protobuf::io::CodedOutputStream* codedOutput = new
> > google::protobuf::io::CodedOutputStream(fileOutput);
>
> > codedOutput->WriteVarint32(message1.ByteSize());
> > message1.SerializeToCodedStream(codedOutput);
> > // also tried snap1.SerializeWithCachedSizes(codedOutput)
>
> > close(fd);
>
> > Thanks!
>
> > --
> > You received this message because you are subscribed to the Google Groups
> > "Protocol Buffers" group.
> > To post to this group, send email to prot...@googlegroups.com.
> > To unsubscribe from this group, send email to

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> > .