I'm doing some work in C with the R_ExternalPointer interface, and having some seg fault problems. I expect the crash is my fault, bad pointer in my code causing a fault later etc, but I'm curious about the point of failure. R almost always falls over in a call to unzReadCurrentFile following a burst of disk activity. I'm definitely not doing anything that would call that explicitly, and I don't notice the bursts of disk activity in similar work without using my package. Any idea what might be causing a compressed file read? Something to do with lazy loading, maybe? I've tried disabling it in the package description without success. This is R 2.0.0 on NetBSD/i386. Mark <><
Prof Brian Ripley
2004-Nov-08 13:45 UTC
[R] Extension provokes crash in unzReadCurrentFile
On Mon, 8 Nov 2004, Mark White wrote:> I'm doing some work in C with the R_ExternalPointer > interface, and having some seg fault problems. I expect the > crash is my fault, bad pointer in my code causing a fault > later etc, but I'm curious about the point of failure. > > R almost always falls over in a call to unzReadCurrentFile > following a burst of disk activity. I'm definitely not > doing anything that would call that explicitly, and I don't > notice the bursts of disk activity in similar work without > using my package. > > Any idea what might be causing a compressed file read?It's not a compressed file read, but rather from the interface for unz() connections to zip files. That is very unlikely to be used on a non-Windows system, so if that really is being called this looks like considerable internal corruption.> Something to do with lazy loading, maybe? I've tried > disabling it in the package description without success. > > This is R 2.0.0 on NetBSD/i386.-- Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, stats.ox.ac.uk/~ripley University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595