qt - QProcess read and write -

i trying read , write qprocess right now. made little test program takes input , redisplays on screen in loop. here code qt

  qstring path = "./test";          tcd = new qprocess(this);         qstringlist args;         args << "";         tcd->start(path,args);          if(!tcd->waitforstarted(3000))         {             stdoutput->append("<h1><font color=red>there problem starting software, please try running program again.</font></h1>");          }         tcd->write("hello\n");         tcd->write("hello\n");         tcd->write("hello\n");         tcd->write("hello\n");         //tcd->write("quit\n");  qobject::connect(tcd, signal(readyreadstandardoutput()), this, slot(appendtextbox())); 

this won't work unless send last quit command (which terminates test program).

here's read command:

void tcd2_gui::appendtextbox(){     stdoutput->append("new output available: \n");     qbytearray newdata = tcd->readallstandardoutput();     stdoutput->append(qstring::fromlocal8bit(newdata)); } 

if send quit, output program @ once, including have sent it.

what doing wrong here?

as per request, here code program:

int main(int argc[], char* argv[]){     printf("welcome!\n");     char* input = malloc(160);     gets(input);      while(strcmp(input,"quit") != 0)     {         printf("got input %s\n", input);         gets(input);      }  } 

from doc:

certain subclasses of qiodevice, such qtcpsocket , qprocess, asynchronous. means i/o functions such write() or read() return immediately, while communication device may happen when control goes event loop. qiodevice provides functions allow force these operations performed immediately, while blocking calling thread , without entering event loop.

...

waitforbyteswritten() - function suspends operation in calling thread until 1 payload of data has been written device.

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calling these functions main, gui thread, may cause user interface freeze.

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