[dev.fuzz] testing: use exit status 70 for worker errors (not crashes)
If a worker process encounters an error communicating with the
coordinator, or if the setup code reports an error with F.Fail
before calling F.Fuzz, exit with status 70. The coordinator will report
these errors and 'go test' will exit non-zero, but the coordinator
won't record a crasher since the problem is not in the code being
fuzzed.
The coordinator also detects unexpected terminations before the worker
calls F.Fuzz by sending a ping RPC. If the worker terminates before
responding to the ping RPC, the coordinator won't record a crasher.
Exit codes are chosen somewhat arbitrary, but in the Advanced Bash
Scripting Guide, 70 is "internal software error" which is applicable
here. 70 is also ASCII 'F'.
Change-Id: I1e676e39a7b07c5664efaaa3221d055f55240fff
Reviewed-on: https://go-review.googlesource.com/c/go/+/297033
Trust: Jay Conrod <jayconrod@google.com>
Trust: Katie Hockman <katie@golang.org>
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Katie Hockman <katie@golang.org>