Re: [Openexr-devel] How can I modify the function of openexr

[Gonzalo Garramuno]

On 27/11/14 11:53, Yan wrote:
> dear all,
>
> As title, I want to modify the function of openexr.
> I try to modify the source code of ImfPizCompressor.cpp, only add one
> line: printf("start wavelet encoding\n");, and then build the openexr
> library.
> But after I build the openexr library and write an test code, the
> sentence that I expect to output is not output.
> So, whether the result means that I don't modify the function
> successfully?
> And, how can I modify the function of openexr?
You should try printing to stderr so that the output does not get cached.

#include <stdio.h>

void func()
{
fprintf( stderr, "Start wavelet encoding\n" );
}

or in C++:

#include <iostream>

void func()
{
std::cerr << "Start wavelet encoding" << std::endl;
}

Also if you are doing this on windows, you need to make sure there's a 
console to output to (and not write a windows application, but a console 
one).

Don't take it personally, but note that if you are having trouble with 
this it is a sign that you might not be ready to change the openexr code.