ORacle 写 blob字段 出错 ，求大神指点

代码 如下：
bool ZzOcciDynaset::blobWrite(Blob* blob,std::stringstream* pIStream)
{
      if (blob == NULL || blob->isNull())
     {
           return false;
    }
   if (NULL == pIStream)
  {
          return false;
 }
 try
 {
         oracle::occi::Stream* pStream = blob->getStream();
        pIStream->seekg(0, std::ios::end);
        unsigned long filesize = pIStream->tellg(); 
        pIStream->seekg(0, std::ios::beg);
       if (filesize == 0)
     {
           return false;
     }    std::string strbuffer;
    strbuffer.resize(1024);
    unsigned long totalwritten = 0;
    unsigned long amtread = 0;
    while(totalwritten != filesize)
    {
           pIStream->read((char*)(strbuffer.c_str()), 1024);
           amtread = pIStream->gcount();
          if (amtread == 0)
         {
                break;
          }        程序 挂在这里 ：
       pStream->writeBuffer((char*)(strbuffer.c_str()),amtread);
       totalwritten = totalwritten + amtread;
    }
    char* c = (char*)"";
    pStream->writeLastBuffer(c,0);
    blob->closeStream(pStream);
 }
catch(oracle::occi::SQLException ex)
{
       ZZLOG(eException, "ZzOcciDynaset::blobWrite(Blob* blob,std::stringstream* pIStream) failed!::ErrorCode::" + 
      CommonData::toString(ex.getErrorCode()) + " failed Mesage：" + ex.getMessage());
     return false;
}
catch(...)
{
        ZZLOG(eException, "ZzOcciDynaset::blobWrite(Blob* blob,std::stringstream* pIStream) failed!");
        return false;
}
 return true;
}