使用poll系统调用时,我发现一个stange行为。 我有以下代码片段。在Linux中调查系统调用的错误行为
struct pollfd myPollfds[nCount];
ACE_Time_Value selectTime;
selectTime.set(60);
myPollfds[0].fd = rtrrmEvent[0];
myPollfds[0].events = POLLIN | POLLRDHUP | POLLHUP | POLLERR;
myPollfds[0].revents = 0;
myPollfds[1].fd = rtrfeEvent[0];
myPollfds[1].events = POLLIN | POLLRDHUP | POLLHUP | POLLERR;
myPollfds[1].revents = 0;
myPollfds[2].fd = _h[msclient_pos];
myPollfds[2].events = POLLIN | POLLRDHUP | POLLHUP | POLLERR;
myPollfds[2].revents = 0;
myPollfds[3].fd = holdTimeEvent[0];
myPollfds[3].events = POLLIN | POLLRDHUP | POLLHUP | POLLERR;
myPollfds[3].revents = 0;
ACE_Time_Value sleepTime(0,20000);
while(isRunning() && !_stopRequested)
{
ACE_OS::sleep(sleepTime);
for(int i = 0; i < 4; i++)
myPollfds[i].revents = 0;
waitResult = ACE_OS::poll (myPollfds, nCount, &selectTime);
if(waitResult == -1) // poll failed
{
DEBUG("%s", "poll failed");
continue;
}
else if(waitResult == 0) // Time out
{
//Do something .
}
char nodata[256];
for(short i = 0; i < nCount; i++)
if(myPollfds[i].revents == POLLIN)
{
if(i == rtrrm_pos)
{
// Stop channel
}
else if(i == rtrfe_pos) // 'rtrfe' command
{
DEBUG("%s", "fe issued");
}
else if(i == msclient_pos || waitResult == 0)
{
//Do something
}
else if(i == holdTime_pos)
{
DEBUG("%s", "Hold issued");
}
}
else
{
DEBUG("polling failed with with myPollfds[i].revents == %d",myPollfds[i].revents);
}
的问题是,我得到一些时间: “轮询失败与myPollfds [I] .revents == 0” : “轮询失败与myPollfds [I] .revents == 8193”
民意调查并未等待fd的设定。 任何人都可以帮忙吗?
-1 for blaming linux。 –
我不是在责怪Linux,我很气急地知道我在做什么错..多数民众赞成它 – samairtimer