utilities: Printing, reading and writing compiled function objects

Description

moveDLL moves the DLL used by a compiled function to a user defined location.

writeCFunc saves a CFunc object after the DLL has been moved to the desired location using moveDLL.

readCFunc reads a CFunc object that has been saved using writeCFunc.

The print and code methods respectively print the entire object or only the code parts.

Usage

moveDLL(x, ...)
# S4 method for CFunc
moveDLL(x, name, directory, unload = FALSE, overwrite = FALSE, verbose = FALSE)
writeCFunc(x, file)
readCFunc(file)
# S4 method for CFunc
print(x)
# S4 method for CFuncList
print(x)
# S4 method for CFunc
code(x, linenumbers = TRUE)
# S4 method for CFuncList
code(x, linenumbers = TRUE)

Value

Function readDynLib returns a CFunc object.

Function writeDynLib returns the name of the .CFunc file that was created.

Arguments

x: A CFunc or CFuncList object as created by cfunction
name: The base of the file name that the DLL should be moved to. The file name extension will depend on the operating system used
directory: The directory that the DLL should be written to
unload: In case the new path constructed from name and directory points to a loaded DLL, should we unload it?
overwrite: In case there is a file at the new path constructed from name and directory should we overwrite that file?
verbose: Should we print a message stating where the DLL was copied if the operation was successful?
file: The file path for writing and reading the object generated by cfunction. Consider using a file name extension like .rda or .RData to indicate that this is a serialized R object.
linenumbers: If TRUE all code lines will be numbered.
...: May be used in future methods

Author

Karline Soetaert and Johannes Ranke

Details

If you move the DLL to a user defined location with moveDLL, this will keep an on-disk copy of the DLL which will prevent it from being lost at session termination - unless written to the session tempdir. Saving and reloading the CFunc object with standard tools like save or saveRDS will still loose the pointer to the DLL. However, when the DLL has been moved using moveDLL, CFunc objects can be saved by writeCFunc and restored by readCFunc.

Examples

Run this code


x <- as.numeric(1:10)
n <- as.integer(10)

code <- "
      integer i
      do 1 i=1, n(1)
    1 x(i) = x(i)**3
"
cubefn <- cfunction(signature(n="integer", x="numeric"), code,
  convention=".Fortran")
code(cubefn)

cubefn(n, x)$x

if (FALSE) {
# The following code is exempted from the automated tests of example code, as
# it writes to the users home directory.
# The following writes the DLL, e.g. cubefn.so on Linux/Unix or cubefn.dll
# on Windows
moveDLL(cubefn, name = "cubefn", directory = "~")
path <- file.path("~", "cubefn.rda")
writeCFunc(cubefn, path)
rm(cubefn)

# Now you can start a fresh R session and load the function
library(inline)
path <- file.path("~", "cubefn.rda")
cfn <- readCFunc(path)
cfn(3, 1:3)$x
}

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