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                         I have downloaded R tree from http://libspatialindex.github.com/ Since on running ./autogen.sh I was getting file/folder not found, therefore I downloaded the file autogen.sh from the github repository given below: Now when I run ./autogen.sh I am getting "Permission denied" And if I run sh ./autogen.sh I am getting: 
Please suggest what should I do now  | 
                
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                                     My first guess would be that "Permission denied" error happens because your not allowed to run ./autogen.sh So, to fix your problem, you would need to run "chmod u+x autogen.sh" to change the file permissions and allow yourself to run it. To illustrate, I created a small script called hi.sh and put it in my current working directory. Notice the x in "-rwxr--r--" below. 
-rw-r--r-- 1 Tom None 25 Feb 28 22:44 hi.sh 
-bash: ./hi.sh: Permission denied 
-rwxr--r-- 1 Tom None 25 Feb 28 22:44 hi.sh 
Hello $  |