On 17 March 2012 at 14:34, Dan Kelley wrote:
| I am having trouble handing "raw" data to a C function, using "cfunction", as
demonstrated in the function and output pasted below. Can anyone suggest what
I'm doing incorrectly? Thanks. Dan Kelley [Dalhousie University].
Don't use the .C convention:
R> library(inline)
R>
R> code <- 'Rprintf("inside f(), b is 0X%x\\n", *b);'
R> f <- cfunction(sig=signature(b="raw"),
+ body=code,
+ convention=".C")
R> b <- as.raw(0x0f)
R> for (i in 1:5)
+ f(b)
inside f(), b is 0X90
inside f(), b is 0X80
inside f(), b is 0X70
inside f(), b is 0X60
inside f(), b is 0X30
R>
R> f2 <- cfunction(sig=signature(b="raw"), body='
+ Rprintf("inside f(), b is 0X%x\\n", AS_RAW(b));
+ return(R_NilValue);
+ ')
R> b <- as.raw(0x0f)
R> for (i in 1:5)
+ f2(b)
inside f(), b is 0X39bf9e8
inside f(), b is 0X39bf9e8
inside f(), b is 0X39bf9e8
inside f(), b is 0X39bf9e8
inside f(), b is 0X39bf9e8
R>
R>
Dirk
--
"Outside of a dog, a book is a man's best friend. Inside of a dog, it is too
dark to read." -- Groucho Marx
______________________________________________
[email protected] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
