BTC price in November 2012
When bitcoin first appeared in 2009, its price was less than 1 cent. One dollar could be converted into 1300 bitcoins, that is to say, seven yuan could be converted into 1300 bitcoins
on May 5, 2017, bitfinex, an overseas digital currency trading platform, quoted a price. Bitcoin once hit US $1700, about RMB 11737
extended information:
in China, some Taobao stores have also begun to accept the use of bitcoin, and businesses will graally increase
in October 2013, the first bitcoin quarterly, one bit, was released
on October 15, 2013, the network accelerator service of the network announced its support for bitcoin
on October 26, 2013, btcmini reported that GBL was hacked
on October 31, 2013, Lei Teng, a famous Internet lawyer, proposed the event of "filing a case to investigate the closure of GBL bitcoin trading platform as soon as possible", analyzed the "value function" and "use function" of bitcoin, and bitcoin should be governed by relevant laws
on December 5, 2013, notice of the Ministry of instry and information technology of the people's Bank of China, China Banking Regulatory Commission, China Securities Regulatory Commission and China Insurance Regulatory Commission on preventing bitcoin risk: bitcoin is a specific virtual commodity; Bitcoin trading is a kind of commodity trading on the Internet. Ordinary people have the freedom to participate in it at their own risk
on September 4, 2017, the announcement of the people's Bank of China Central Network Information Office, Ministry of instry and information technology, State Administration for Instry and commerce, China Banking Regulatory Commission, China Securities Regulatory Commission and China Insurance Regulatory Commission on preventing the risk of token issuance financing: it is prohibited to engage in token issuance financing activities (ICO)
the trading platform shall not engage in the exchange business between legal tender and token, or virtual currency, or buy or sell token or virtual currency as a central counter party, or provide pricing, information intermediary and other services for token or virtual currency
on November 2, 2018, the people's Bank of China released the 12th topic of China financial stability report 2018, which talked about "encrypted assets"
In 2009, when bitcoin first appeared, one dollar could buy 1300 bitcoins. In 2010, it was only $0.003. In November 2013, the highest price created by bitcoin reached 8000 yuan for the first time. In 2017, bitcoin's price rose wildly. In this year, bitcoin once created the highest price in history, with the highest value of about 20000 US dollars
that is to say, a bitcoin costs about 130000 yuan. According to the proportion, bitcoin has soared by 2.73 million times in eight years, becoming a well deserved proct with huge profits. According to the data of coindesk digital currency trading platform, the price of bitcoin once fell below $6000 in 18 years, and it has dropped 70% compared with the highest value of $20000 in 2017
with the decline of bitcoin, many digital currencies have been affected, with a decline of more than 10%. It has been less than 10 years since the development of digital currency. Many large enterprises can't compare with it. It can be seen that the future of digital currency is worth looking forward to
The first half: on November 28, 2012, the 210000 block was excavated, and the block reward was halved for the first time, and the block reward was 25btc
the second half: on July 10, 2016, starting from the 420.000 block, the bitcoin reward of each block was halved to 12.5btc
the third half: on May 12, 2020, bitcoin reward will be halved to 6.25btc
the next half: on May 9, 2024, bitcoin reward will be halved to 3.125btc
on November 28, 2012, BTC was halved for the first time, from $2.01 to $1178, an increase of nearly 600 times
on July 10, 2016, BTC halved for the second time, from $163.65 to $19800, an increase of more than 120 times
BTC is expected to halve for the third time in May 2020.
There's always a reason for
1. Transfer platform: the current domestic trading is closed, and it can be transferred to foreign trading platforms
2. Cash withdrawal: users who do not want to hold bitcoin can make cash withdrawal
Third, storage: users who do not want to trade but continue to hold coins can save them in bitcoin wallets such as coin packets.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <netdb.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/ip.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <netpacket/packet.h>
#include <net/ethernet.h>
#include <net/if.h>
#include <arpa/inet.h>
#include <errno.h>
/* 接收缓冲区大小 */
#define RCV_BUF_SIZE 1024 * 5
/* 接收缓冲区 */
static int g_iRecvBufSize = RCV_BUF_SIZE;
static char g_acRecvBuf[RCV_BUF_SIZE] = {0};
/* 物理网卡接口,需要根据具体情况修改 */
static const char *g_szIfName = "eth1";
/* 以太网帧封装的协议类型 */
static const int g_iEthProId[] = { ETHERTYPE_PUP,
ETHERTYPE_SPRITE,
ETHERTYPE_IP,
ETHERTYPE_ARP,
ETHERTYPE_REVARP,
ETHERTYPE_AT,
ETHERTYPE_AARP,
ETHERTYPE_VLAN,
ETHERTYPE_IPX,
ETHERTYPE_IPV6,
ETHERTYPE_LOOPBACK
};
static const char g_szProName[][24] = {
"none", "xerox pup", "sprite", "ip", "arp",
"rarp", "apple-protocol", "apple-arp",
"802.1q", "ipx", "ipv6", "loopback"
};
/* 输出MAC地址 */
static void ethmp_showMac(const int iType, const char acHWAddr[])
{ int i = 0;
if (0 == iType)
{
printf("SMAC=[");
}
else
{
printf("DMAC=[");
}
for(i = 0; i < ETHER_ADDR_LEN - 1; i++)
{
printf("%02x:", *((unsigned char *)&(acHWAddr[i])));
}
printf("%02x] ", *((unsigned char *)&(acHWAddr[i])));
}
/* 物理网卡混杂模式属性操作 */
static int ethmp_setPromisc(const char *pcIfName, int fd, int iFlags)
{ int iRet = -1;
struct ifreq stIfr;
/* 获取接口属性标志位 */
strcpy(stIfr.ifr_name, pcIfName);
iRet = ioctl(fd, SIOCGIFFLAGS, &stIfr);
if (0 > iRet)
{ perror("[Error]Get Interface Flags");
return -1;
}
if (0 == iFlags)
{ /* 取消混杂模式 */
stIfr.ifr_flags &= ~IFF_PROMISC;
}
else
{ /* 设置为混杂模式 */
stIfr.ifr_flags |= IFF_PROMISC;
}
iRet = ioctl(fd, SIOCSIFFLAGS, &stIfr);
if (0 > iRet)
{ perror("[Error]Set Interface Flags");
return -1;
}
return 0;
}
/* 获取L2帧封装的协议类型 */
static char *ethmp_getProName(const int iProNum)
{ int iIndex = 0;
for(iIndex = 0; iIndex < sizeof(g_iEthProId) / sizeof(g_iEthProId[0]); iIndex++)
{ if (iProNum == g_iEthProId[iIndex])
{
break;
}
}
return (char *)(g_szProName[iIndex + 1]);
}
/* Init L2 Socket */
static int ethmp_initSocket()
{ int iRet = -1;
int fd = -1;
struct ifreq stIf;
struct sockaddr_ll stLocal = {0};
/* 创建SOCKET */
fd = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
if (0 > fd)
{ perror("[Error]Initinate L2 raw socket");
return -1;
}
/* 网卡混杂模式设置 */
ethmp_setPromisc(g_szIfName, fd, 1);
/* 设置SOCKET选项 */
iRet = setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &g_iRecvBufSize,sizeof(int));
if (0 > iRet)
{ perror("[Error]Set socket option");
close(fd);
return -1;
}
/* 获取物理网卡接口索引 */
strcpy(stIf.ifr_name, g_szIfName);
iRet = ioctl(fd, SIOCGIFINDEX, &stIf);
if (0 > iRet)
{ perror("[Error]Ioctl operation");
close(fd);
return -1;
}
/* 绑定物理网卡 */
stLocal.sll_family = PF_PACKET;
stLocal.sll_ifindex = stIf.ifr_ifindex;
stLocal.sll_protocol = htons(ETH_P_ALL);
iRet = bind(fd, (struct sockaddr *)&stLocal, sizeof(stLocal));
if (0 > iRet)
{ perror("[Error]Bind the interface");
close(fd);
return -1;
}
return fd;
}
/* 解析Ethernet帧首部 */
static int ethmp_parseEthHead(const struct ether_header *pstEthHead)
{ unsigned short usEthPktType;
if (NULL == pstEthHead)
{ return -1;}
/* 协议类型、源MAC、目的MAC */
usEthPktType = ntohs(pstEthHead->ether_type);
printf(">>>\nEth-Pkt-Type:0x%04x(%s) ", usEthPktType, ethmp_getProName(usEthPktType));
ethmp_showMac(0, pstEthHead->ether_shost);
ethmp_showMac(1, pstEthHead->ether_dhost);
return 0;
}
/* 解析IP数据包头 */
static int ethmp_parseIpHead(const struct ip *pstIpHead)
{ struct protoent *pstIpProto = NULL;
if (NULL == pstIpHead)
{ return -1;}
/* 协议类型、源IP地址、目的IP地址 */
pstIpProto = getprotobynumber(pstIpHead->ip_p);
if(NULL != pstIpProto)
{ printf("\nIP-Pkt-Type:%d(%s) ", pstIpHead->ip_p, pstIpProto->p_name); }
else
{ printf("\nIP-Pkt-Type:%d(%s) ", pstIpHead->ip_p, "None");}
printf("SAddr=[%s] ", inet_ntoa(pstIpHead->ip_src));
printf("DAddr=[%s]\n", inet_ntoa(pstIpHead->ip_dst));
return 0;
}
/* 数据帧解析函数 */
static int ethmp_parseFrame(const char *pcFrameData)
{ int iRet = -1;
struct ether_header *pstEthHead = NULL;
struct ip *pstIpHead = NULL;
/* Ethnet帧头解析 */
pstEthHead = (struct ether_header*)g_acRecvBuf;
iRet = ethmp_parseEthHead(pstEthHead);
if (0 > iRet)
{ return iRet;}
/* IP数据包类型 */
pstIpHead = (struct ip *)(pstEthHead + 1);
iRet = ethmp_parseIpHead(pstIpHead);
return iRet;
}
/* 捕获网卡数据帧 */
static void ethmp_startCapture(const int fd)
{ int iRet = -1;
socklen_t stFromLen = 0;
/* 循环监听 */
while(1)
{ /* 清空接收缓冲区 */
memset(g_acRecvBuf, 0, RCV_BUF_SIZE);
/* 接收数据帧 */
iRet = recvfrom(fd, g_acRecvBuf, g_iRecvBufSize, 0, NULL, &stFromLen);
if (0 > iRet)
{ continue;}
/* 解析数据帧 */
ethmp_parseFrame(g_acRecvBuf);
}
}
/* Main */
int main(int argc, char *argv[])
{ int iRet = -1;
int fd = -1;
/* 初始化SOCKET */
fd = ethmp_initSocket();
if(0 > fd) {
return -1;
}
/* 捕获数据包 */
ethmp_startCapture(fd);
/* 关闭SOCKET */
close(fd);
return 0;
}
编译命令
gcc -o a a.c
./a
实现效果图
...
>>>Eth-Pkt-Type:0x0800(ip) SMAC=[00:1a:92:ef:b6:dd] DMAC=[00:24:7e:dc:99:18] IP-Pkt-Type:6(tcp) SAddr=[192.168.0.111] DAddr=[192.168.0.100]
>>> Eth-Pkt-Type:0x0800(ip) SMAC=[00:24:7e:dc:99:18] DMAC=[00:1a:92:ef:b6:dd] IP-Pkt-Type:6(tcp) SAddr=[192.168.0.100] DAddr=[192.168.0.111]
>>> Eth-Pkt-Type:0x0800(ip) SMAC=[00:24:7e:dc:99:18] DMAC=[00:1a:92:ef:b6:dd] IP-Pkt-Type:1(icmp) SAddr=[192.168.0.100] DAddr=[192.168.0.111]
>>> Eth-Pkt-Type:0x0800(ip) SMAC=[00:1a:92:ef:b6:dd] DMAC=[00:24:7e:dc:99:18] IP-Pkt-Type:1(icmp) SAddr=[192.168.0.111] DAddr=[192.168.0.100]
>>> Eth-Pkt-Type:0x0800(ip) SMAC=[00:1a:92:ef:b6:dd] DMAC=[00:24:7e:dc:99:18] IP-Pkt-Type:6(tcp) SAddr=[192.168.0.111] DAddr=[192.168.0.100]
...
because of the open source code of bitcoin, anyone can manufacture and issue it, which leads to the fact that it is controlled by large consortia, making the market price unstable
bitcoin has been running for nearly nine years, and it has been hyped too high, so it is not suitable for public investment.