1
我做了一个客户端&服务器建立通过套接字TCP连接，我试图通过套接字发送二进制数据，但我只能派出TXT或PDF文件，我没有运气exe文件，我使用fread和fseek来读取文件并将其分割成缓冲区。当我读取整个exe文件时，它会被成功发送，但是当我分割它时，它会被发送损坏！通过TCP发送二进制文件插座Ç
我读了一些关于套接字的书，但我仍然不太了解，并且有一些问题。
可以在一个send（）中发送整个文件吗？或者我应该继续以小块形式发送它？
此外，为什么EXE文件在我发送块时被损坏？
谢谢！ （C语言）
客户端代码：
int bufSize = 10000;
int sentBytes = 0;
FILE * pFile;
long remainingBytes;
char * buffer;
size_t result;
pFile = fopen ("D:\\file.exe" , "rb");
fseek (pFile , 0 , SEEK_END);
remainingBytes = ftell (pFile);
rewind (pFile);
int bufferSize = remainingBytes > bufSize ? bufSize : remainingBytes;
buffer = (char*) malloc (sizeof(char)*bufferSize);
send(Socket, (char*)&remainingBytes, 4, 0);
while(remainingBytes > 0)
{
fseek (pFile , sentBytes , SEEK_SET);
result = fread(buffer,1,bufferSize,pFile);
if(bufferSize < remainingBytes)
{
send(Socket, buffer, bufferSize, 0);
}
else
{
send(Socket, buffer, remainingBytes, 0);
bufferSize = remainingBytes;
}
remainingBytes -= bufferSize;
sentBytes += bufferSize;
}
服务器代码（C＃）
try
{
int bufferSize = 200;
int len = 0;
int receivedBytes = 0;
int remainingBytes = len;
byte[] length = new byte[4];
//byte[] imgBuf = new byte[bufferSize];
int current = 0;
List<byte[]> coming = new List<byte[]>();
sockets[number].Receive(length,4,0);
len = BitConverter.ToInt32(length, 0);
remainingBytes = len;
bufferSize = len < bufferSize ? len : bufferSize;
while(receivedBytes < len)
{
if (remainingBytes > bufferSize)
{
coming.Add(new byte[bufferSize]);
//imgBuf = new byte[bufferSize];
sockets[number].Receive(coming[current], bufferSize, 0);
}
else
{
coming.Add(new byte[remainingBytes]);
//imgBuf = new byte[remainingBytes];
sockets[number].Receive(coming[current], remainingBytes, 0);
bufferSize = remainingBytes;
}
remainingBytes -= bufferSize;
receivedBytes += bufferSize;
current++;
//Array.Clear(imgBuf, 0, imgBuf.Length);
}
using (var stream = new FileStream(@"C:\receivedFile.exe",FileMode.Create))
{
using (var binaryWriter = new BinaryWriter(stream))
{
foreach (byte[] buffer in coming)
{
binaryWriter.Write(buffer);
}
}
}
}
catch (Exception ex)
{ this.setText(ex.Message, textBox2); }
编辑：感谢您的帮助，我得到它的工作:)
try
{
int bufferSize = 1024 * 100;
int len = 0;
int receivedBytes = 0;
int remainingBytes = len;
int reached = 0;
byte[] length = new byte[4];
byte[] imgBuf = new byte[bufferSize];
int current = 0;
sockets[number].Receive(length,4,0);
len = BitConverter.ToInt32(length, 0);
remainingBytes = len;
bufferSize = len < bufferSize ? len : bufferSize;
imgBuf = new byte[len];
while (reached < len)
{
reached += sockets[number].Receive(imgBuf, receivedBytes, remainingBytes, 0);
remainingBytes = len - reached;
receivedBytes = reached;
current++;
//Array.Clear(imgBuf, 0, imgBuf.Length);
}
using (var stream = new FileStream(@"C:\putty.exe",FileMode.Create))
{
using (var binaryWriter = new BinaryWriter(stream))
{
binaryWriter.Write(imgBuf);
}
}
Array.Clear(imgBuf, 0, imgBuf.Length);
}
catch (Exception ex)
{ this.setText(ex.Message, textBox2); }
如果你从文件系统传输整个文件，你应该使用['的TransmitFile（）']（http://msdn.microsoft.com/en-us/library/ms740565（VS.85）。 aspx）（如果在Windows上）或['sendfile（）']（http://www.kernel.org/doc/man-pages/online/pages/man2/sendfile.2.html）（如果在Unix上） – millimoose
感谢您的回答，但正如我所提到的，当我发送整个文件时，我完全没有问题。只有当我尝试以大块发送时才会出现此问题。 –
我想说的是，不应该通过在内存中缓冲文件来从文件中发送文件，以便从性能的角度出发，无论文件是否在大块中 - 使用其中一种函数会更高效。 – millimoose