(SOLVED)How To Change Date and Time in linux system based from Qt Based Application

[praveen0991kr]

Dear ,
I am trying to to change date and time of system from qt application but there is no effect from QDate and QTime class ;
when I am access currentDate() and currentTime() it access system time.

Praveen

[Chris Kawa]

QDate and QTime are not used to change any system settings. They are just data formats to hold information about date and time.

What you need is a OS specific feature. For Windows it's a "SetLocalTime":http://msdn.microsoft.com/en-us/library/ms724936.aspx API. On Linux there's a "date":http://linux.die.net/man/1/date command which you can call with "QProcess":http://qt-project.org/doc/qt-5.1/qtcore/qprocess.html .
You might of course need to run your app with enough access privileges to be able to do that.

[koahnig]

welcome to devnet

The static methods "currentDate":http://qt-project.org/doc/qt-5.0/qtcore/qdate.html#currentDate and "currentTime":http://qt-project.org/doc/qt-5.0/qtcore/qtime.html#currentTime read only

You may use "setDate":http://qt-project.org/doc/qt-5.0/qtcore/qdate.html#setDate and "setTime":http://qt-project.org/doc/qt-5.0/qtcore/qtime.html#setHMS but AFAIK those will not change the system clock permanently either.

[praveen0991kr]

I am using Linux environment Based device. Using @ setDate @ and @ setTime @ also I am i am not able to set my clock when I use @ currentTime @ and current date it is the system time not that what i have set through @ setTime and setDate @

@Chris
If it can be done with Qprocess pls tell me how
Did I can make a object for the same to access or there is specific commands to set and read current time as per we have set.

i have gone through the link as per mentioned on http://www.qtcentre.org/archive/index.php/t-44384.html
http://www.cyberciti.biz/faq/howto-set-date-time-from-linux-command-prompt/

but i want to access through program Qt application

[koahnig]

As Chris confirmed it is not possible through Qt directly.
When using QProcess you basically use a standard command, a linux command in your case, to change the system clock. Like you would do on a terminal prompt. However, you will have to have the superuser rights.
With QProcess you can basically launch any command and application available on a system.
In addition to the links already provided, you may also check out the "QProcess documentation.":http://qt-project.org/doc/qt-5.0/qtcore/qprocess.html

[houmingc]

If there is ubuntu system header and source file (API downloadable), this is still achievable. Right?
The question is where to get the header and source file.

Is there a method to input sudo password rather than wait for interactive command. is setuid, seteuid, setgid able to do the job.

[praveen0991kr]

Hello Frnds ,
Thanks for your replies ;
I am able to change the date and time as well :--) Yes thanks to koahhning for refering QProcess documentation it really helped ;

QProcess allow to access command line or terminal to change the Date and Time In my case the Embedded device I am working on having kernal 3.2 and from command line I can able to change the date and time ;

1. System Clock;
   date command
2. Hardware Clock;
   hwclock command

it does require sudo command;

[houmingc]

I found command chmod u+s hello will give the app root access.
http://stackoverflow.com/questions/6119254/how-to-run-a-script-with-root-authority-in-linux