README.md

In ufo-org/ufo-r-operators: Operator overloads for UFO vectors

UFO R Operators

This package contains a collection of operator overloads for use with UFO vectors: R API of the UFO native vectors, and UFO sandboxed R vectors.

The package provides operators and helper functions for UFO vectors:

• unary operators: -, +, !
• binary arithmetic operators: *, +, -, %%, /, %/%
• comparison operators: <, <=, >, >=, >, >=, ==, !=, |, &
• subsetting operators: [, [<-
• subscript derivation ufo_subscript
• in-place mutation: ufo_mutate

Warning: UFOs are under active development. Some bugs are to be expected, and some features are not yet fully implemented.

System requirements

• R 3.6.0 or higher
• Linux 4.3 or higher (we currently do not support other operating systems)

Prerequisites

Check if your operating system restricts who can call userfaultfd:

cat /proc/sys/vm/unprivileged_userfaultfd

0 means only privileged users can call userfaultfd and UFOs will only work for privileged users. To allow unprivileged users to call userfaultfd:

sysctl -w vm.unprivileged_userfaultfd=1

Building

Before building, retrievew the code of a submodule:

git submodule update --init --recursive

To update the submodule, pull it.

cd include/ufo_r && git pull origin main && cd ../..

Install the package with R. This compiles and properly install the package.

R CMD INSTALL --preclean .

You can also build the project with debug symbols by setting (exporting) the UFO_DEBUG environmental variable to 1.

UFO_DEBUG=1 R CMD INSTALL --preclean .

Testing

Check the package and display all errors:

_R_CHECK_TESTS_NLINES_=0 R CMD check .

Troubleshooting

Operation not permitted

syscall/userfaultfd: Operation not permitted
error initializing User-Fault file descriptor: Invalid argument
Error: package or namespace load failed for ‘ufos’:
 .onLoad failed in loadNamespace() for 'ufos', details:
  call: .initialize()
  error: Error initializing the UFO framework (-1)

The user has insufficient privileges to execute a userfaultfd system call.

One likely culprit is that a global sysctl knob vm.unprivileged_userfaultfd to control whether userfaultfd is allowed by unprivileged users was added to kernel settings. If /proc/sys/vm/unprivileged_userfaultfd is 0, do:

sysctl -w vm.unprivileged_userfaultfd=1

ufo-org/ufo-r-operators documentation built on May 18, 2022, 12:40 a.m.