[pcp] pmRegisterDerived return values

[Ken McDonell]

On 18/01/16 20:28, Marko Myllynen wrote:
> Hi,
>
> In https://bugzilla.redhat.com/show_bug.cgi?id=1286733 two Python PMAPI
> pmRegisterDerived related issues were reported and they were already
> fixed but I think we all kind of forgot the bigger picture.
>
> Consider this example (from the BZ):
>
>          try:
>              self.context.pmRegisterDerived("foo", "rat(disk.dev.read)")
>          except:
>              print self.context.pmDerivedErrStr()
>
> Here pmDerivedErrStr returns nothing. Is this expected or should
> pmDerivedErrStr be improved to return always something understandable in
> case of errors?
>
> Thanks,
>

Looks like a Python wrapper issue ... libpcp and friends get it right it 
would appear.

kenj at bozo:~/src/pcp/qa$ pminfo -c /tmp/eek foo
[/tmp/eek:1] Error: pmRegisterDerived(foo, ...) syntax error
  rat(disk.dev.read)
     ^
Error: foo: Unknown metric name
kenj at bozo:~/src/pcp/qa$ cat /tmp/eek
foo = rat(disk.dev.read)