How can I get a difference between two DateTime intervals in micro and nano seconds?

[J.Hilk]

You can use

#include <QElapsedTimer>

its has the function

qint64 QElapsedTimer::nsecsElapsed() const

that is nano seconds since last started.
Available since Qt 4.7.

[SGaist]

That's what I would have proposed except his environment uses Qt 4.3.2

[J.Hilk]

@SGaist
Oh, I missed that, sorry.
For some reason all I thought was "pre Qt5.0 so it fits" .

[mrjj]

Hi
He is trying the boost chrono as @VRonin suggest but
im not sure building it with VS 2005 is great joy. ? :)

[VRonin]

@mrjj The current release uses C++11 but boost version 1.47.0 does not. I also think boost::chrono and std::chrono are the same thing

[mrjj]

@VRonin
Ah and such old version might have makefile for Vs 2005 included.
We cross fingers :=)

[srikanth]

can i use chrono in VS 2005 , am unable to get nanoseconds is there anyway to get nanoseconds in vs 2005 & Qt 4.3.2

[jsulm]

@srikanth As @VRonin said you can use Boost 1.47.0 (boost::chrono: https://theboostcpplibraries.com/boost.chrono).

[srikanth]

@jsulm i downloaded the boost.zip file from this link
[http://www.boost.org/users/history/version_1_63_0.html]

unzip them and then add something like INCLUDEPATH += C:/boost/boost_1_63_0/ to my pro file , if i run this code then it is getting error like this "fatal error LNK1104: cannot open file 'libboost_chrono-vc80-mt-gd-1_63.lib' " so what can i do now ? to get this lib file .

[mrjj]

@srikanth
Try the 1.47.0 one.
1_63 might be too new for VS 2005.

[jsulm]

@srikanth You need to link to the library mentioned in the error message:

LIBS += -LPATH_TO_BOOST_LIBS -lboost_chrono-vc80-mt-gd-1_63

[srikanth]

QueryPerformanceCounter is giving microseconds
but not in exactly
i have one doubt in this
please check my code once
https://paste.ofcode.org/gg6d6ESDmJHDkxxQmkUkbN

[SGaist]

It depends on the source. You have all the explanations here.