# Does glFinish behave like regular OpenGL on PowerVR?

**URL:** <https://forums.imgtec.com/t/does-glfinish-behave-like-regular-opengl-on-powervr/2619>\
**Category:** PowerVR Insider\
**Created:** [April 3, 2018, 7:32am UTC](https://forums.imgtec.com/t/does-glfinish-behave-like-regular-opengl-on-powervr/2619 "2018-04-03T07:32:58Z")\
**Posts on this page:** 1\
**Showing post:** 3

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**Author:** ![desperado](https://avatars.discourse-cdn.com/v4/letter/d/3ab097/32.png) [@desperado](https://forums.imgtec.com/u/desperado)\
**Post date:** [April 4, 2018, 7:07pm UTC](https://forums.imgtec.com/t/does-glfinish-behave-like-regular-opengl-on-powervr/2619/3 "2018-04-04T19:07:10Z")

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Hello,

I dug a little further and what irritated me was this post by JoeDavis from 6 years ago where he claims that the behaviour of glFlush and glFinish ist platform dependent:

> [@Synchronized output when rendering to an FBO with an eglImage attached](https://forums.imgtec.com/t/synchronized-output-when-rendering-to-an-fbo-with-an-eglimage-attached/1607/2):
>
> I maybe found a solution, but I think that it is a workaround for a bug and shouldn’t be necessary. If I bind the FBO and do a glReadPixels(0,0,1,1,…) (which costs me about 30-40ms) the problem is gone. Not sure about the OpenGL spec, but I would assume that glFinish or glFlush should be enough to have valid data in memory.

I know it is possible to influence the behaviour of these functions for certain platforms, usually via powervr.ini. However, does PVR require board designers to provide standard-conformant behaviour as default?

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