Why does "enable-shared failed" happen on libjpeg build for os X?

Question

I'm trying to install libjpeg on os X to fix a problem with the Python Imaging Library JPEG setup.

I downloaded libjpeg from http://www.ijg.org/files/jpegsrc.v7.tar.gz

I then began to setup the config file

cp /usr/share/libtool/config.sub .
cp /usr/share/libtool/config.guess .
./configure –enable-shared

However, the enable-shared flag didn't seem to work.

$ ./configure –-enable-shared
configure: WARNING: you should use --build, --host, --target
configure: WARNING: invalid host type: –-enable-shared
checking build system type... Invalid configuration `–-enable-shared': machine `–-enable' not recognized
configure: error: /bin/sh ./config.sub –-enable-shared failed

I've done lot's of google searches and I can't figure out where the error is or how to work around this error.

Answer 1

I had copied the code from a blog.

The flag character there was not a hyphem , it just looked like one:

ord("–")

TypeError: ord() expected a character, but string of length 3 found

I changed it to a proper hypen and it works fine.