Extract 1 file from tar.gz with bash
I echo Jefromi's answer, with the addition of including the path to the file if you have directories in the tar file (this may seem obvious to some, but it wasn't initially clear to me how to specify the directory structure).
For example, if you did the tar at the src/ directory, and blah.txt was under release1/shared/, you would go back to the src/ directory (if you want it untarred at the same place)
tar -xzf tar.gz release1/shared/blah.txtIf you don't remember the directory structure of your tar file (I'm a little disorganized and sometimes forget where I did the tar), you can always
tar -tzf tar.gzto see the contents, canceling out (Ctrl+C) once you get an idea of your directory structure.