Error installing pdf-extract

[radeksvarz]

Can we avoid using the build tools, please?

C:\Temp>gem install pdf-extract
ERROR: Error installing pdf-extract:
The 'libsvm-ruby-swig' native gem requires installed build tools.

Please update your PATH to include build tools or download the DevKit
from 'http://rubyinstaller.org/downloads' and follow the instructions
at 'http://github.com/oneclick/rubyinstaller/wiki/Development-Kit'

[iamgp]

Can't you just use them?

[amiraliakbari]

Same problem, +1
Even with build tools, installation of libsvm-ruby-swig fails on new versions of Ubuntu (and probably other distributions bundling newer versions of libsvm). The issue is reported to libsvm-ruby-swig (tomz/libsvm-ruby-swig#7) but that project seems to not be maintained anymore. Is there any alternative to libsvm-ruby-swig?