getDLLRegisteredRoutines {base}R Documentation

Reflectance Information for C/Fortran routines in a DLL

Description

This function allows us to query the set of routines in a DLL that are registered with R to enhance dynamic lookup, error handling when calling native routines, and potentially security in the future. This function provides a description of each of the registered routines in the DLL for the different interfaces, i.e. .C, .Call, .Fortran and .External.

Usage

getDLLRegisteredRoutines(dll, addNames = TRUE)

Arguments

dll

a character string or DLLInfo object. The character string specifies the file name of the DLL of interest, and is given without the file name extension (e.g., the ‘.dll’ or ‘.so’) and with no directory/path information. So a file ‘MyPackage/libs/MyPackage.so’ would be specified as ‘⁠MyPackage⁠’.

The DLLInfo objects can be obtained directly in calls to dyn.load and library.dynam, or can be found after the DLL has been loaded using getLoadedDLLs, which returns a list of DLLInfo objects (index-able by DLL file name).

The DLLInfo approach avoids any ambiguities related to two DLLs having the same name but corresponding to files in different directories.

addNames

a logical value. If this is TRUE, the elements of the returned lists are named using the names of the routines (as seen by R via registration or raw name). If FALSE, these names are not computed and assigned to the lists. As a result, the call should be quicker. The name information is also available in the NativeSymbolInfo objects in the lists.

Details

This takes the registration information after it has been registered and processed by the R internals. In other words, it uses the extended information.

There is a print method for the class, which prints only the types which have registered routines.

Value

A list of class "DLLRegisteredRoutines" with four elements corresponding to the routines registered for the .C, .Call, .Fortran and .External interfaces. Each is a list (of class "NativeRoutineList") with as many elements as there were routines registered for that interface.

Each element identifies a routine and is an object of class "NativeSymbolInfo". An object of this class has the following fields:

name

the registered name of the routine (not necessarily the name in the C code).

address

the memory address of the routine as resolved in the loaded DLL. This may be NULL if the symbol has not yet been resolved.

dll

an object of class DLLInfo describing the DLL. This is same for all elements returned.

numParameters

the number of arguments the native routine is to be called with.

Author(s)

Duncan Temple Lang duncan@wald.ucdavis.edu

References

‘Writing R Extensions’ manual for symbol registration.

Duncan Temple Lang (2001). “In Search of C/C++ & FORTRAN Routines”. R News, 1(3), 20–23. https://www.r-project.org/doc/Rnews/Rnews_2001-3.pdf.

See Also

getLoadedDLLs, getNativeSymbolInfo for information on the entry points listed.

Examples

dlls <- getLoadedDLLs()
getDLLRegisteredRoutines(dlls[["base"]])

getDLLRegisteredRoutines("stats")
[Package base version 4.4.1 Index]