realpath をソースコードビルドする ref: http://qiita.com/boscoworks/items/024d41d17277529b054b

file0.txt

wget http://github.com/dtjm/realpath/raw/master/realpath.c -P /usr/local/share/downloaded/

file1.txt

gcc -o /usr/local/src/realpath /usr/local/share/downloaded/realpath.c

file2.txt

chmod 0755 /usr/local/src/realpath

file3.txt

sudo ln -s /usr/local/src/realpath /usr/local/bin/realpath

file4.txt

sudo rm -r /usr/local/share/downloaded/realpath.c
sudo rm -r /usr/local/src/realpath
sudo rm -r /usr/local/bin/realpath