Forum: GNU Radio cmake max version test?

It turns out that gr-qtgui isn't compatible with the QWT 6 API.  It 
works with QWT 5.2.1 and 5.1.2; I don't know about 5.0.2 or earlier.

Does anyone know if there a (simple) way in CMake to check that the 
library is -not- of a specific version?  For example:

find_package(Qwt "< 6")

where the "< 6" is used for version checking.  We could use 
'find_package(Qwt 5)' but then I don't know if the gr-qtgui is 
compatible with QWT 4.2.0 (and, I'm not inclined to do so given that 
that version dates to 2004).  QWT does not install a PKGCONFIG, not a 
"qwt-config" type of script; as far as I can tell, the only way to 
verify its version is by either checking that of the installed library 
or its headers (and, for cross-OS compatibility I'd guess the latter).

I'd love to see an updated gr-qtgui, but the QWT 6 API is quite 
different than that from 5 & there are a number of changes that would be 
required in the GR code -- so, probably not anytime soon given the 
number of changes that would be required.

Anyway, wondering if anyone knows of a simple solution.  Thanks! - MLD

On Thu, Nov 1, 2012 at 12:01 PM, Michael Dickens <mlk@alum.mit.edu> 
wrote:
> Anyway, wondering if anyone knows of a simple solution.  Thanks! - MLD
gr-qtgui /should/ be compatible with QWT6. I've been running it on
QWT6 on my systems since 12.04 came out. If there are specific
problems, we can patch it.

If you look inside the code, there are quite a few places where you'll
see #if's checking for the QWT version to do the right thing.

Tom

On Nov 1, 2012, at 12:04 PM, Tom Rondeau <tom@trondeau.com> wrote:
> gr-qtgui /should/ be compatible with QWT6. I've been running it on
> QWT6 on my systems since 12.04 came out. If there are specific
> problems, we can patch it.
>
> If you look inside the code, there are quite a few places where you'll
> see #if's checking for the QWT version to do the right thing.

I just activated qwt 6.0.1, and this time it worked.  So, ignore what I 
said about compatibility; the issue was with my end somehow.  I had 
looked at the code and thought it seemed compatible, but for some reason 
it just didn't work until now.  Ah well; that happens sometimes :) - MLD

On Thu, Nov 1, 2012 at 9:39 PM, Michael Dickens <mlk@alum.mit.edu> 
wrote:
> On Nov 1, 2012, at 12:04 PM, Tom Rondeau <tom@trondeau.com> wrote:
>> gr-qtgui /should/ be compatible with QWT6. I've been running it on
>> QWT6 on my systems since 12.04 came out. If there are specific
>> problems, we can patch it.
>>
>> If you look inside the code, there are quite a few places where you'll
>> see #if's checking for the QWT version to do the right thing.
>
> I just activated qwt 6.0.1, and this time it worked.  So, ignore what I said 
about compatibility; the issue was with my end somehow.  I had looked at the code 
and thought it seemed compatible, but for some reason it just didn't work until 
now.  Ah well; that happens sometimes :) - MLD

Good to know! It was a pain when they moved to version 6 and took some
time to convert over, and we still miss things sometimes when we're
working on qtgui, but I've been trying to be good about checking
against both version 5 and 6 before we release new stuff.

Tom