Can't install via pip with Virtualenv

Below is the error I get when I run pip:

serkan$ rm -r mysite
serkan$ pwd
/Users/serkan/Desktop/Python Folder
serkan$ virtualenv mysite 
New python executable in mysite/bin/python
Installing setuptools............done.
Installing pip...............done.
serkan$ source mysite/bin/activate
(mysite)serkan$ pip install pinax
-bash: /Users/serkan/Desktop/Python Folder/mysite/bin/pip: "/Users/serkan/Desktop/Python: bad interpreter: No such file or directory
(mysite)serkan$ python pip install pinax
python: can't open file 'pip': [Errno 2] No such file or directory
(mysite)serkan$ python pip install Pinax
python: can't open file 'pip': [Errno 2] No such file or directory
(mysite)serkan$ python pip install Pinax
python: can't open file 'pip': [Errno 2] No such file or directory
(mysite)serkan$ python pip install Pinax
python: can't open file 'pip': [Errno 2] No such file or directory
(mysite)serkan$ python pip 
python: can't open file 'pip': [Errno 2] No such file or directory
(mysite)serkan$ pip
-bash: /Users/serkan/Desktop/Python Folder/mysite/bin/pip: "/Users/serkan/Desktop/Python: bad interpreter: No such file or directory
(mysite)serkan$ pip install Pinax
-bash: /Users/serkan/Desktop/Python Folder/mysite/bin/pip: "/Users/serkan/Desktop/Python: bad interpreter: No such file or directory
(mysite)serkan$ 

Create your virtualenv environment within a path without spaces. This is why it is happening:

When you create an environment, it sets up a bin directory. In that bin directory are all the executables relating to the environment. Some are scripts. As you may know, hashbangs are used to tell the system what interpreter to use to run the script. You may see this at the top of scripts often:

#!/usr/bin/env python

If the script is at /tmp/test.py, that tells the system to run this command to execute the script:

/usr/bin/env python /tmp/test.py

In your case, virtualenv is creating scripts like this:

#!/tmp/oh no/bin/python

When the system tries to execute that, it will try to execute the command /tmp/oh with the arguments no/bin/python and /tmp/test.py. /tmp/oh does not exist, so it fails.

For those running into this issue, I discovered that the length of the path could cause issues as well, without using any spaces (Ubuntu 12.04):

virtualenv /home/user/some/very/longer/path/without/spaces/etc/venv

failed, while

virtualenv /home/user/some/very/long/path/without/spaces/etc/venv

worked just fine, see Alex's comment below

pip command won't work if:

• You have not installed pip in your system. (you have to install pip first in your system before you can use it in virtualenv. To install pip on Ubuntu, use command sudo apt-get install python-pip or sudo apt-get install python3-pip)
• The path to your virtual environment folder contains space(s).(Example: /home/username/my folder name with spaces/newvirtualenv)
• The path to your virtual environment folder is too long. Example: /home/username/mytoobigpath/somefolder/anotherfolder/someanotherfolder/someanotherfolderagain/myvirtualenv. (Try renaming parent folders with smaller names)

If you can't rename folders or change path for some reason, goto yourvirtualenvfolder/bin (using cd command) and then try ./python pip install packagename.

icktoofay is correct about the cause.

To use pip with virtualenv in a directory with spaces, edit /path/to/env/bin/pip, replacing the shebang at the top with #!/usr/bin/env python (or #!/usr/bin/env pypy if you're using pypy).

Note that virtualenv changes your environment such that /usr/bin/env python refers to the python defined by the virtualenv.