Rvm install ruby-2.4.1

Question

I had downloaded the rvm before with the ruby and the rails but it gave a problem that I could not solve, so I took the gems and imploded in the rvm, but now that I ask to install the ruby it does not, and when I give it A ruby -v appears that already is installed, the version 2.4.1, the same happens with the rails in version 4.2.6. what I do? What's happening?

rvm install ruby-2.4.1
Searching for binary rubies, this might take some time.
Found remote file https://rvm_io.global.ssl.fastly.net/binaries/ubuntu/16.04/x86_64/ruby-2.4.1.tar.bz2
Checking requirements for ubuntu.
Installing requirements for ubuntu.
Updating system..
Installing required packages: gawk, libyaml-dev, autoconf, libgdbm-dev, libncurses5-dev, automake, bison, libffi-dev....
Error running 'requirements_debian_libs_install gawk libyaml-dev autoconf libgdbm-dev libncurses5-dev automake bison libffi-dev',
showing last 15 lines of /usr/local/rvm/log/1497634607_ruby-2.4.1/package_install_gawk_libyaml-dev_autoconf_libgdbm-dev_libncurses5-dev_automake_bison_libffi-dev.log
  autoconf-archive gnu-standards autoconf-doc bison-doc gawk-doc ncurses-doc
  libyaml-doc
The following NEW packages will be installed:
  autoconf automake bison gawk libbison-dev libffi-dev libgdbm-dev
  libncurses5-dev libsigsegv2 libyaml-dev m4
0 upgraded, 11 newly installed, 0 to remove and 13 not upgraded.
Need to get 0 B/2,462 kB of archives.
After this operation, 9,047 kB of additional disk space will be used.
dpkg: warning: 'ldconfig' not found in PATH or not executable
dpkg: warning: 'start-stop-daemon' not found in PATH or not executable
dpkg: error: 2 expected programs not found in PATH or not executable
Note: root's PATH should usually contain /usr/local/sbin, /usr/sbin and /sbin
E: Sub-process /usr/bin/dpkg returned an error code (2)
++ return 100
++ return 100
Requirements installation failed with status: 100.

root@ubuntu:~# ruby -v
ruby 2.4.1p111 (2017-03-22 revision 58053) [x86_64-linux-gnu]
root@ubuntu:~# rails -v
Rails 4.2.6

Answer 1

I skirted the problem by changing the version of rails, like this:

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', github: 'rails/rails', branch: '4-2-stable'