On Nov 21, 2010, at 17:42 , Pen Ttt wrote: > thinks everyone.this right way is : > sudo wget ftp.ruby-lang.org/pub/ruby/1.9/ruby-1.9.2-p0.tar.bz2 > sudo tar jxvf ruby-1.9.2-p0.tar.bz2 > cd /home/pt/ruby-1.9.2-p0 > sudo ./configure --prefix=3D/usr/local/ruby > sudo make > sudo make install > sudo ln -s /usr/local/ruby/bin/ruby /usr/bin/ruby > sudo ln -s /usr/local/ruby/bin/gem /usr/bin/gem > sudo gedit /etc/environment >=20 > = PATH=3D"/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/= games:/usr/local/ruby/bin" Again, don't blindly use sudo! This should work just as well, and safer too: cd wget ftp.ruby-lang.org/pub/ruby/1.9/ruby-1.9.2-p0.tar.bz2 tar jxvf ruby-1.9.2-p0.tar.bz2 cd ruby-1.9.2-p0 ./configure --prefix=3D/usr/local/ruby && make && sudo make install sudo ln -s /usr/local/ruby/bin/ruby /usr/bin/ruby sudo ln -s /usr/local/ruby/bin/gem /usr/bin/gem and since you're making symbolic links to a directory that is already in = your PATH, you don't need to edit your PATH in /etc/environment.