QT client data of BTC

1. If you want to contribute to the bitcoin network, it's a good choice to run a full node to synchronize the block data; If you just want to use bitcoin, you don't need a full node wallet at all. You just need to install a new wallet. The better one in China is the coin pack.

2. This problem I have encountered, I 2003 system under the wallet, found that the wallet data file is wrong! Thought it was a problem with the 2003 system! Specially modified 64 bit win7, error still! I don't know what's wrong! I feel that I have been following the upgrade of bitcoin wallet all the time! Up to now, it's 1.49M, but no matter how I make it, it's all a mistake! At first, delete all the block chains, only one wallet data file! After the update is completed, you can see that it is normal for a period of time. If you open the wallet for a long time, you will report an error again. After the error is reported, unless the reconstructed data is displayed normally for a period of time again! But still can't solve the problem! Back to the original just built wallet file, just set the password, just set up the collection address data backup out to use, the result is no problem! And all bitcoin is still there! By contrast, when using the 1.49M wallet data file, the record of the latest received bitcoin can't be written in, and then it's OK to look at the data backup file. Anyway, there are no recent transaction records, but there are so many bitcoins, so the error should be here! But I don't know how to solve this problem, I can only use the original wallet backup, fortunately, there is a 300 K backup at the beginning, otherwise it's finished! Now there is no problem, this problem has to be reported to the official!

3. Search: why do bitcoin clients always prompt fatal errors when synchronizing data? Please refer to the debug file for details.

4. This is a drawback of bitcoin. You can't delete it. You have to resynchronize after deleting it. Of course, you can use light wallet, but its security is not as good as this one

5. The wallet file downloaded from bitcoin QT client is wallet.dat, and the wallet file downloaded from multibit client is multibit.wallet. The file name, size and format of these two files are different, so how to switch? If you don't need to save the original address, send the coin directly to the multibit address

6. No backup dat file. If you delete it, you lose it.

7. The old version has been installed for some time. Recently, the latest version has been released, but it still can't be synchronized. The computers at home and at work can't be synchronized. Check the original post& gt;

8. First, answer the first question. Read and write can be implemented in many ways. Write and read are just one of them. In the previous function, clientconnection - & gt; Write (block) is implemented by calling the write method in the qtcpsocket class. If you want to call the read and write methods in the class without using this method, that's the second question you ask. The role of in and out, where in and out change the sending and receiving of packets in the socket into the form of data flow, Qdatastream in (tcpsocket) for example, this sentence is to pass the instance object of tcpsocket as a file descriptor to qdatastream, and then in & gt& gt; Blocksize is an operation equivalent to read, which is to read the data stream. This is out & lt& lt; ( Quint16) (block. Size () - sizeof (quint16)) is a write. In fact, for example, sending and receiving through serial port, reading and writing files, socket communication and so on, we use C language to write, abstract and operate file descriptors. We can use write and read to do both. Therefore, in fact, the first method and the second method are the same, depending on which method you choose. For the third problem, please refer to out & lt& lt; ( This method sends the data after receiving it
please give me a score...

9. I think this is the biggest problem of BTC at present. The current transaction volume is still very small. If the transaction volume increases by 100 times, the client data will become a headache, that is, the transaction volume does not rise. If the wallet keeps rising and reaches the P level, synchronization will become impossible. The designer of BTC has considered this problem, but it's a pity that the problem has not been solved after he left.

10. The following program has been tested and can meet your requirements< br />
#include < stdio.h>< br />#include < stdlib.h>< br />#include < string.h>

int main()
{
/ / output HTTP header
printf & quot; Content-type: text/plain\ n\ n");

/ / from content_ Take the value of
int n = ATOI (getenv & quot; CONTENT_ LENGTH"));< br /> printf("% d\ n", n);< br /> char buf[20];< br /> memset(buf, 0, sizeof(buf));
/ / read data from stdin standard input stream
fgets (buf, N, stdin)

/ / output
printf & quote; Hi, this is CGI with c\ n");< br /> printf("% s\ n", buf);< br />
return 0;
}

you know the general process, but some details are not clear. When reading data from stdin, you first need to know how long data to read, and the length is stored in "content"_ Length 'in the whole environment variable. In addition, fgets function is used to read data from stdin. Scanf is not used to read data in network communication.