[Qt-interest] newbie: application locks up

[john doe]

On Fri, May 1, 2009 at 2:47 AM, chandrasekar wagmare <sekarwagmare at gmail.com
> wrote:

>
> use this two signals in QProcess() :
>  void readyReadStandardOutput();     //when a stdoutput is available
>  void readyReadStandardError();         //when a stderror is available
>
> and use  QByteArray readAllStandardOutput(); and readAllStandardError() ;
> to read the std output or error of the external process in a QString and
> display it in the box;
>
>
This is great! thanks a ton!


>
> ay 1, 2009 at 1:19 PM, john doe <thebiggestbangtheory at gmail.com> wrote:
>
>>
>>
>> On Fri, May 1, 2009 at 12:46 AM, chandrasekar wagmare <
>> sekarwagmare at gmail.com> wrote:
>>
>>>
>>> u have two ways, invoking an external program using QProcess()
>>> and if u dont want the gui part freeze use QThread() .
>>>
>>
>> awesome! I will look them up.. and since we are on the topic how can I set
>> up a 2-way communication with the external program to display any error msgs
>> in a text box or something?
>>
>> Thanks again
>>
>>
>>> On Fri, May 1, 2009 at 1:08 PM, john doe <thebiggestbangtheory at gmail.com
>>> > wrote:
>>>
>>>> Hello all,
>>>>              Still relative newbie with Qt. I have made my first form
>>>> containing combo buttons, lineedits and whatnot :-). I am facing a problem
>>>> though regarding calling an external program from within the C++ Qt code.
>>>>
>>>> I have a ubuntu system and want to invoke a shell script which does some
>>>> string manipulations on a large file. I used system() within the C++ code to
>>>> do it and it runs. The problem is that when I press a button to start the
>>>> external program, if it takes 10 minutes to finish, the button seems to be
>>>> depressed for this duraion. Basically, like waiting for the program to
>>>> finish. How can I make the button not be depressed for this complete
>>>> duration so that I can possibly start another instance of the external
>>>> program by pressing a button on the main form.
>>>>
>>>> I am not an expert programmer, but I think this smells of asynchronous
>>>> calls..right? Any insight would be greatly appreciated :-).
>>>>
>>>> I did try using a & at the end of the external program I am invoking but
>>>> that does not help. Nothing runs. I am using kdesudo to start the external
>>>> program as it requires certain privileges.
>>>>
>>>> Also I tried to use a progress bar with minimum and max set to 0 to
>>>> continuosly work while the external program is running and it does not seem
>>>> to work. Any pointers to threads/articles?
>>>>
>>>> Thanks in  advance.
>>>>
>>>> _______________________________________________
>>>> Qt-interest mailing list
>>>> Qt-interest at trolltech.com
>>>> http://lists.trolltech.com/mailman/listinfo/qt-interest
>>>>
>>>>
>>>
>>>
>>> --
>>> WAGMARE
>>>
>>
>>
>
>
> --
> WAGMARE
>
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