HPCC-33288 Support zero len remote compressed files

[jakesmith]

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Testing:

[github-actions]

Jira Issue: https://hpccsystems.atlassian.net//browse/HPCC-33288

Jirabot Action Result:
Assigning user: jake.smith@lexisnexisrisk.com
Workflow Transition To: Merge Pending
Updated PR

[mckellyln]

Looks good.
Should the same change be added to write() ?

[mckellyln]

Any idea why the CI failure - Test Build / build-gh_runner-macos-14 / build-gh_runner (pull_request) ?

[jakesmith]

Should the same change be added to write() ?

the read check prevents a crash (when len is null and data is null).
write will handle 0/null successfully so would be an extra check for a unusual optimization, prob. not worth it.

[jakesmith]

Any idea why the CI failure - Test Build / build-gh_runner-macos-14 / build-gh_runner (pull_request) ?

not really. @GordonSmith thinks may be an issue related to the runner version being bumped. The action is being rerun.

[mckellyln]

ok, great - then this is ready for merge.

[github-actions]

Jirabot Action Result:
Added fix version: 9.6.78
Added fix version: 9.8.54
Workflow Transition: 'Resolve issue'