So I now have the full diagnostic output: 

Assertion ((svtype)((sv)->sv_flags & 0xff)) != 0xff failed: file "sv.c
+", line 5400 at /usr/local/lib/perl5/5.10.1/mach/IO/Handle.pm line 48
+0.

[download]
This is indeed in sv_clear as some mentioned earlier.

In reply to Re^3: Request help for work around for bug in perl 5.10.1 by babel17
in thread [Solved] Request help for work around for bug in perl 5.10.1 by babel17

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