⑴ 如何用C语言编个测网速的小工具
直接用 ping 就可以了。
C语言 用 system("ping ....."); 调用。
ping 命令参数 查 用 ping /? 帮助文件
1、system函数：
原型：int system(const char * command)；
功能：执行 dos(windows系统) 或 shell(Linux/Unix系统) 命令，参数字符串command为命令名;
说明：在windows系统中，system函数直接在控制台调用一个command命令。在Linux/Unix系统中，system函数会调用fork函数产生子进程，由子进程来执行command命令，命令执行完后随即返回原调用的进程；
头文件：stdlib.h；
返回值：命令执行成功返回0，执行失败返回-1。
2、例程：
#include<stdio.h>
#include<stdlib.h>
int main(){
system("del C:\\123.txt");//在控制台中，执行命令del C:\\123.txt，删除C盘目录下的123.txt文件
return 0;
}
⑵ 用C语言如何限制一个进程的网速
C语言做不到，这个涉及到驱动级编程，要写设备驱动程序。
⑶ C语言与网络问题 高手进
ping命令是dos命令可以创建一个cmd进程,然后建立两个管道用来得到结果 实现.
下面是一个网络编程的实例, Syn扫描器代码,可以作为参考.
基本可以看为是 ping命令的实现
//getallIP.cpp
#include <winsock2.h>
#include <stdio.h>
#pragma comment(lib,"ws2_32.lib")
int main()
{
////////////////
// 初始化 Windows sockets API.
//
WORD wVersionRequested = MAKEWORD(2, 2);
WSADATA wsaData;
if (WSAStartup(wVersionRequested, &wsaData)) {
printf("WSAStartup failed %s\n", WSAGetLastError());
return 0;
}
//////////////////
// 获得主机名.
//
char hostname[256];
int res = gethostname(hostname, sizeof(hostname));
if (res != 0) {
printf("Error: %u\n", WSAGetLastError());
return 0;
}
printf("hostname=%s\n", hostname);
////////////////
// 根据主机名获取主机信息.
//
hostent* pHostent = gethostbyname(hostname);
if (pHostent==NULL) {
printf("Error: %u\n", WSAGetLastError());
return 0;
}
//////////////////
// 解析返回的hostent信息.
//
hostent& he = *pHostent;
printf("name=%s\naliases=%s\naddrtype=%d\nlength=%d\n",
he.h_name, he.h_aliases, he.h_addrtype, he.h_length);
sockaddr_in sa;
//根据 he.h_addr_list[nAdapter]是否为空来获取所有IP地址
for (int nAdapter=0; he.h_addr_list[nAdapter]; nAdapter++) {
memcpy ( &sa.sin_addr.s_addr, he.h_addr_list[nAdapter],he.h_length);
// 输出机器的IP地址.
printf("Address [%d%]: %s\n",nAdapter, inet_ntoa(sa.sin_addr)); // 显示地址串
}
//////////////////
// 终止 Windows sockets API
//
WSACleanup();
return 0;
}
//mstcpip.h
// Copyright (C) Microsoft Corporation, 1996-1999
#if _MSC_VER > 1000
#pragma once
#endif
/* Argument structure for SIO_KEEPALIVE_VALS */
struct tcp_keepalive {
u_long onoff;
u_long keepalivetime;
u_long keepaliveinterval;
};
// New WSAIoctl Options
#define SIO_RCVALL _WSAIOW(IOC_VENDOR,1)
#define SIO_RCVALL_MCAST _WSAIOW(IOC_VENDOR,2)
#define SIO_RCVALL_IGMPMCAST _WSAIOW(IOC_VENDOR,3)
#define SIO_KEEPALIVE_VALS _WSAIOW(IOC_VENDOR,4)
#define SIO_ABSORB_RTRALERT _WSAIOW(IOC_VENDOR,5)
#define SIO_UCAST_IF _WSAIOW(IOC_VENDOR,6)
#define SIO_LIMIT_BROADCASTS _WSAIOW(IOC_VENDOR,7)
#define SIO_INDEX_BIND _WSAIOW(IOC_VENDOR,8)
#define SIO_INDEX_MCASTIF _WSAIOW(IOC_VENDOR,9)
#define SIO_INDEX_ADD_MCAST _WSAIOW(IOC_VENDOR,10)
#define SIO_INDEX_DEL_MCAST _WSAIOW(IOC_VENDOR,11)
//synscan.cpp
#include <winsock2.h>
#include <ws2tcpip.h>
#include <stdio.h>
#include <time.h>
#include "mstcpip.h"
#pragma comment(lib,"ws2_32.lib")
#define SEQ 0x28376839
SOCKET sockRaw = INVALID_SOCKET,
sockListen = INVALID_SOCKET;
struct sockaddr_in dest;
BOOL ScanOK=FALSE;
char *DEST_HOST;
int DEST_PORT;
int DEST_PORTEND;
int play=0;
clock_t start,end;//程序运行的起始和结束时间
float costtime;//程序耗时
typedef struct _iphdr
{
unsigned char h_lenver; //4位首部长度+4位IP版本号
unsigned char tos; //8位服务类型TOS
unsigned short total_len; //16位总长度（字节）
unsigned short ident; //16位标识
unsigned short frag_and_flags; //3位标志位
unsigned char ttl; //8位生存时间 TTL
unsigned char proto; //8位协议 (TCP, UDP 或其他)
unsigned short checksum; //16位IP首部校验和
unsigned int sourceIP; //32位源IP地址
unsigned int destIP; //32位目的IP地址
}IP_HEADER;
typedef struct _tcphdr //定义TCP首部
{
USHORT th_sport; //16位源端口
USHORT th_dport; //16位目的端口
unsigned int th_seq; //32位序列号
unsigned int th_ack; //32位确认号
unsigned char th_lenres; //4位首部长度/6位保留字
unsigned char th_flag; //6位标志位
USHORT th_win; //16位窗口大小
USHORT th_sum; //16位校验和
USHORT th_urp; //16位紧急数据偏移量
}TCP_HEADER;
struct //定义TCP伪首部
{
unsigned long saddr; //源地址
unsigned long daddr; //目的地址
char mbz;
char ptcl; //协议类型
unsigned short tcpl; //TCP长度
}psd_header;
//SOCK错误处理程序
void CheckSockError(int iErrorCode, char *pErrorMsg)
{
if(iErrorCode==SOCKET_ERROR)
{
printf("%s Error:%d\n", pErrorMsg, GetLastError());
closesocket(sockRaw);
ExitProcess(-1);
}
}
//计算检验和
USHORT checksum(USHORT *buffer, int size)
{
unsigned long cksum=0;
while (size > 1)
{
cksum += *buffer++;
size -= sizeof(USHORT);
}
if (size)
{
cksum += *(UCHAR*)buffer;
}
cksum = (cksum >> 16) + (cksum & 0xffff);
cksum += (cksum >>16);
return (USHORT)(~cksum);
}
//IP解包程序
bool DecodeIPHeader(char *buf, int bytes)
{
IP_HEADER *iphdr;
TCP_HEADER *tcphdr;
unsigned short iphdrlen;
iphdr = (IP_HEADER *)buf;
iphdrlen = sizeof(unsigned long) * (iphdr->h_lenver & 0xf);
tcphdr = (TCP_HEADER*)(buf + iphdrlen);
//是否来自目标IP
if(iphdr->sourceIP != dest.sin_addr.s_addr) return false;
//序列号是否正确
if((ntohl(tcphdr->th_ack) != (SEQ+1)) && (ntohl(tcphdr->th_ack) != SEQ)) return false;
//if(tcphdr->th_flag == 20)return true;
//SYN/ACK - 扫描到一个端口
if(tcphdr ->th_flag == 18)
{
printf("\t%d\t open \n",ntohs(tcphdr->th_sport));
return true;
}
return true;
}
void usage(void)
{
printf("\t===================SYN portscaner======================\n");
printf("\[email protected] 2004/7/6===========\n");
printf("\tusage: synscan DomainName[IP] StartPort-EndPort\n");
printf("\tExample: synscan www.163.com 1-139\n");
printf("\tExample: synscan 192.168.1.1 8000-9000\n");
}
DWORD WINAPI RecvThread(LPVOID para)//接收数据线程函数
{
int iErrorCode;
struct hostent *hp;
char RecvBuf[65535]={0};
sockListen = socket(AF_INET , SOCK_RAW , IPPROTO_IP);
CheckSockError(sockListen, "socket");
//设置IP头操作选项
BOOL bOpt = true;
iErrorCode = setsockopt(sockRaw,IPPROTO_IP,IP_HDRINCL,(char *)&bOpt,sizeof(bOpt));
CheckSockError(iErrorCode, "setsockopt()");
//获得本地IP
SOCKADDR_IN sa;
unsigned char LocalName[256];
iErrorCode = gethostname((char*)LocalName,sizeof(LocalName)-1);
CheckSockError(iErrorCode, "gethostname()");
if((hp = gethostbyname((char*)LocalName)) == NULL)
{
CheckSockError(SOCKET_ERROR, "gethostbyname()");
}
memcpy(&sa.sin_addr.S_un.S_addr,hp->h_addr_list[1],hp->h_length);
sa.sin_family = AF_INET;
sa.sin_port = htons(7000);
iErrorCode = bind(sockListen, (PSOCKADDR)&sa, sizeof(sa));
CheckSockError(iErrorCode, "bind");
//设置SOCK_RAW为SIO_RCVALL，以便接收所有的IP包
DWORD dwBufferLen[10] ;
DWORD dwBufferInLen = 1 ;
DWORD dwBytesReturned = 0 ;
iErrorCode=WSAIoctl(sockListen, SIO_RCVALL,&dwBufferInLen, sizeof
(dwBufferInLen),&dwBufferLen, sizeof(dwBufferLen),&dwBytesReturned , NULL , NULL );
CheckSockError(iErrorCode, "Ioctl");
memset(RecvBuf, 0, sizeof(RecvBuf));
//接收数据
for(;;)
{
iErrorCode = recv(sockListen, RecvBuf, sizeof(RecvBuf), 0);
//CheckSockError(iErrorCode, "recv");
DecodeIPHeader(RecvBuf,iErrorCode) ;
}
if(ScanOK)
{
closesocket(sockListen);
return 0;
}
}
void playx(void) // 定义状态提示函数
{
// 进度条
char *plays[12]=
{
" | ",
" / ",
" - ",
" \\ ",
" | ",
" / ",
" - ",
" \\ ",
" | ",
" / ",
" - ",
" \\ ",
};
printf(" =%s=\r", plays[play]);
play=(play==11)?0:play+1;
Sleep(2);
}
//主函数
int main(int argc,char **argv)
{
char *p;
if(argc!=3)
{
usage();
return 0;
}
p=argv[2];//处理端口参数
if(strstr(argv[2],"-"))
{ DEST_PORT=atoi(argv[2]);
for(;*p;)
if(*(p++)=='-')break;
DEST_PORTEND=atoi(p);
if(DEST_PORT<1 || DEST_PORTEND>65535)
{ printf("Port Error!\n");
return 0;
}
}
DEST_HOST=argv[1];
usage();
int iErrorCode;
int datasize;
struct hostent *hp;
IP_HEADER ip_header;
TCP_HEADER tcp_header;
char SendBuf[128]={0};
//初始化SOCKET
WSADATA wsaData;
iErrorCode = WSAStartup(MAKEWORD(2,2),&wsaData);
CheckSockError(iErrorCode, "WSAStartup()");
sockRaw = socket(AF_INET , SOCK_RAW , IPPROTO_IP);
CheckSockError(sockRaw, "socket()");
sockListen = socket(AF_INET , SOCK_RAW , IPPROTO_IP);
CheckSockError(sockListen, "socket");
//设置IP头操作选项
BOOL bOpt = true;
iErrorCode = setsockopt(sockRaw,IPPROTO_IP,IP_HDRINCL,(char *)&bOpt,sizeof(bOpt));
CheckSockError(iErrorCode, "setsockopt()");
//获得本地IP
SOCKADDR_IN sa;
unsigned char LocalName[256];
iErrorCode = gethostname((char*)LocalName,sizeof(LocalName)-1);
CheckSockError(iErrorCode, "gethostname()");
if((hp = gethostbyname((char*)LocalName)) == NULL)
{
CheckSockError(SOCKET_ERROR, "gethostbyname()");
}
memcpy(&sa.sin_addr.S_un.S_addr,hp->h_addr_list[1],hp->h_length);
sa.sin_family = AF_INET;
sa.sin_port = htons(7000);
iErrorCode = bind(sockListen, (PSOCKADDR)&sa, sizeof(sa));
CheckSockError(iErrorCode, "bind");
//获得目标主机IP
memset(&dest,0,sizeof(dest));
dest.sin_family = AF_INET;
dest.sin_port = htons(DEST_PORT);
if((dest.sin_addr.s_addr = inet_addr(DEST_HOST)) == INADDR_NONE)
{
if((hp = gethostbyname(DEST_HOST)) != NULL)
{
memcpy(&(dest.sin_addr),hp->h_addr_list[1],hp->h_length);
dest.sin_family = hp->h_addrtype;
printf("dest.sin_addr = %s\n",inet_ntoa(dest.sin_addr));
}
else
{
CheckSockError(SOCKET_ERROR, "gethostbyname()");
}
}
//开启监听线程
HANDLE Thread=CreateThread(NULL,0,RecvThread,0,0,0);
//填充IP首部
ip_header.h_lenver=(4<<4 | sizeof(ip_header)/sizeof(unsigned long));
//高四位IP版本号，低四位首部长度
ip_header.total_len=htons(sizeof(IP_HEADER)+sizeof(TCP_HEADER)); //16位总长度（字节）
ip_header.ident=1; //16位标识
ip_header.frag_and_flags=0; //3位标志位
ip_header.ttl=128; //8位生存时间TTL
ip_header.proto=IPPROTO_TCP; //8位协议(TCP,UDP…)
ip_header.checksum=0; //16位IP首部校验和
ip_header.sourceIP=sa.sin_addr.s_addr; //32位源IP地址
ip_header.destIP=dest.sin_addr.s_addr; //32位目的IP地址
//填充TCP首部
tcp_header.th_sport=htons(7000); //源端口号
tcp_header.th_lenres=(sizeof(TCP_HEADER)/4<<4|0); //TCP长度和保留位
tcp_header.th_win=htons(16384);
//填充TCP伪首部（用于计算校验和，并不真正发送）
psd_header.saddr=ip_header.sourceIP;
psd_header.daddr=ip_header.destIP;
psd_header.mbz=0;
psd_header.ptcl=IPPROTO_TCP;
psd_header.tcpl=htons(sizeof(tcp_header));
Sleep(500);
printf("\n");
printf("Scaning %s\n",DEST_HOST);
start=clock();//开始计时
for(;DEST_PORT<DEST_PORTEND;DEST_PORT++)
{
playx();
tcp_header.th_dport=htons(DEST_PORT); //目的端口号
tcp_header.th_ack=0; //ACK序列号置为0
tcp_header.th_flag=2; //SYN 标志
tcp_header.th_seq=htonl(SEQ); //SYN序列号
tcp_header.th_urp=0; //偏移
tcp_header.th_sum=0; //校验和
//计算TCP校验和，计算校验和时需要包括TCP pseudo header
memcpy(SendBuf,&psd_header,sizeof(psd_header));
memcpy(SendBuf+sizeof(psd_header),&tcp_header,sizeof(tcp_header));
tcp_header.th_sum=checksum((USHORT *)SendBuf,sizeof(psd_header)+sizeof(tcp_header));
//计算IP校验和
memcpy(SendBuf,&ip_header,sizeof(ip_header));
memcpy(SendBuf+sizeof(ip_header),&tcp_header,sizeof(tcp_header));
memset(SendBuf+sizeof(ip_header)+sizeof(tcp_header),0,4);
datasize=sizeof(ip_header)+sizeof(tcp_header);
ip_header.checksum=checksum((USHORT *)SendBuf,datasize);
//填充发送缓冲区
memcpy(SendBuf,&ip_header,sizeof(ip_header));
//发送TCP报文
iErrorCode=sendto(sockRaw,SendBuf,datasize,0,(struct sockaddr*) &dest,
sizeof(dest));
CheckSockError(iErrorCode, "sendto()");
}
end=clock();//计时结束
ScanOK=TRUE;
printf("Closeing Thread.....\n");
WaitForSingleObject(Thread,5000);
CloseHandle(Thread);
costtime= (float)(end - start) / CLOCKS_PER_SEC; //转换时间格式
printf("Cost time:%f Sec",costtime);//显示耗时
//退出前清理
if(sockRaw != INVALID_SOCKET) closesocket(sockRaw);
WSACleanup();
return 0;
}
⑷ 求助，基于C语言的UDP通信问题发送、接收端口问题
bind一下就可以
int s = socket(AF_INET, SOCK_DGRAM, 0);
struct sockaddr_in local= {0};
local.sin_family = AF_INET;
local.sin_port = htons(60200);
inet_aton("192.168.3.100", (struct in_addr *)&local.sin_addr.s_addr);//换成你的IP地址
bind(s, (struct sockaddr *)&local, sizeof(local));
⑸ 用C语言如何限制网速
你是要用C语言写运行视窗，来执行限制网速命令吗？
其实现在路由器全部都是带这功能的