Discovery ignoring EPERM and ENOBUFS

[osrf-migration]

Original report (archived issue) by Nate Koenig (Bitbucket: Nathan Koenig).

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Prerequisites

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Description

The sendto function in Discovery.hh was generating console error messages. These error messages were causing CI failures, and might be safely ignored. See pull request #379.

Transport seems to functional in the presence of the error message. However, it would be good to spend time to convince ourselves that the error messages are indeed spurious, or find the root cause.

Steps to Reproduce

Pull request #379 has steps to reproduce.

Expected behavior:

No console error message

Actual behavior:

Sporadic output of "Exception sending a multicast message".

Reproduces how often:

Periodically.

Versions

At least Transport 6+

[osrf-migration]

Original comment by Steve Peters (Bitbucket: Steven Peters, GitHub: scpeters).

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There is some discussion about ENOBUFS errors on macOS in the following page, which may or may not be related:

• https://stackoverflow.com/questions/16555101/sendto-dgrams-do-not-block-for-enobufs-on-osx