[MacPorts] #63492: py37-openslide @1.1.2_1: OSError: dlopen(libopenslide.0.dylib, 6): image not found

[MacPorts]

#63492: py37-openslide @1.1.2_1: OSError: dlopen(libopenslide.0.dylib, 6): image
not found
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  Reporter:  DavidBAEpstein           |      Owner:  bgilbert
      Type:  defect                   |     Status:  assigned
  Priority:  Normal                   |  Milestone:
 Component:  ports                    |    Version:  2.7.1
Resolution:                           |   Keywords:
      Port:  openslide, py-openslide  |
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Comment (by DavidBAEpstein):

 Replying to Renee Otten

 That's extremely helpful, and looks promising. I will try that and report
 back, either way.
 I forget how I installed everything, but I certainly did use a mixture of
 conda, pip and port, without an inkling that this could cause problems.
 ...some time later...
 My problem has now gone away. I found a conda requirements file on our
 Github repo, removed my old unsuccessful environment and created the new
 environment, using "conda create" with the -f flag for the requirements
 file. This installs a conda version of pip, so that pip in that
 environment works consistently with conda. I think that conda cannot
 install the openslide binaries from C-code directly, and this has to be
 done by pip (but one must use the conda version of pip). Incidentally,
 although "import openslide" now works, the diff -r between the openslide
 packages on /opt/local and on ~/anaconda3, continues to give an identical
 answer to what I saw before, so my previous "test" using "diff -r" was
 misleading. I think all the binary files are differ for both the failing
 environment and the new successful one. All the other files (python
 programs) are identical.

 Your explanation above is excellent and I hope it will avoid others
 getting into the same pickle (at least in the case of openslide). You have
 pointed out that this has occurred from time to time with other ports.
 What do you think about you adding to the Macports guide(s) a short
 section with your wisdom about Macports and virtual environments, and
 associated hazards that must be avoided?

-- 
Ticket URL: <https://trac.macports.org/ticket/63492#comment:10>
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