ruby - How to resolve LoadError: cannot load such file -- ffi_c -

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i know how resolve next error seen when executed require command on console after installed ruby 2.2.1 windows installer , ruby gem 2.4.6.

loaderror: cannot load such file -- ffi_c         c:/ruby22-x64/lib/ruby/site_ruby/2.2.0/rubygems/core_ext/kernel_req uire.rb:54:in `require'

is dll?

if read requirement documentation ffi, can see:

you need sane building environment in order compile extension. @ minimum, need:

  • a c compiler (e.g. xcode on osx, gcc on else)
  • libffi development library - commonly in libffi-dev or libffi-devel

this means gem not pre-compiled, , has compile code when installs. in turn means if running on pc need install ruby development kit windows, aka 'devkit', can downloads page on rubyinstaller site

download , install devkit first, open new command line window followed by:

gem install ffi

refer details: https://stackoverflow.com/a/7988119/3035830


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