From ripley at stats.ox.ac.uk  Wed Feb 21 14:32:10 2007
From: ripley at stats.ox.ac.uk (Prof Brian Ripley)
Date: Wed, 21 Feb 2007 13:32:10 +0000 (GMT)
Subject: [Rd] R unstable and crashes after executing .C
In-Reply-To: <5FF3F11444E3A9439191AA1EDCB69A17B86201@icosrvmail01.ICO.SCS.local>
References: <5FF3F11444E3A9439191AA1EDCB69A17B86201@icosrvmail01.ICO.SCS.local>
Message-ID: <Pine.LNX.4.64.0702211331250.10793@auk.stats>

Please do as I suggested in my reply to your message to R-help!
And do read the posting guide and not send HMTL mail.

On Wed, 21 Feb 2007, Sole Acha, Xavi wrote:

> Dear R listers,
>
>
>
> I have developed a C function to be executed from R through the ".C" interface. After doing dyn.load, the function executes properly and I get the results. However, after executing my function, R seems to get unstable and crashes (giving a segmentation fault and exiting) whenever I try to do ANYTHING with a relatively large object (creating a new one or even just writing the name of an existing one).
>
>
>
> I use R 2.4.0 under a Linux machine with 1 GB RAM. Below there is an example of execution, so you can get an idea of what is happening:
>
>
>
> --------------------
>
> dyn.load("my_C_module.so");
>
> res <- .C("my_C_function",.....); #The function executes fine and res is ok
>
> dyn.unload("my_C_module.so") #I know this isn't strictly necessary
>
>
>
> #Here R is still running, but when I execute:
>
>
>
> m <- matrix(0,1000,100); #I try to create a new object and R crashes
>
>
>
> *** caught segfault ***
>
> address 0x10, cause 'memory not mapped'
>
>
>
> Traceback:
>
> 1: matrix(0, 1000, 100)
>
>
>
> Possible actions:
>
> 1: abort (with core dump)
>
> 2: normal R exit
>
> 3: exit R without saving workspace
>
> 4: exit R saving workspace
>
> --------------------
>
>
>
> Although I tell R to abort and give me the core dump, it doesn't succeed in doing so.
>
>
>
> I would be grateful if anyone could tell me what could be the problem with my C function that makes R behave this way?
>
>
>
> Thank you very much in advance, and apologies for this long email.
>
>
>
> Xavier Sol?.
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>
>
>
>
>
> 	[[alternative HTML version deleted]]
>
>

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.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


[Rd] R unstable and crashes after executing .C
Prof Brian Ripley