Comment 0 for bug 830492

It should be possible to download while installing, or download 2 things at once.

Currently an apt-get command with '--download-only' will lock apt (/var/lib/dpkg/lock). Synaptic even locks apt just by being open!

Examples:
* I might be updating my system. The update is still in the download stage, and I want to download and install a small package for something. Currently I would have to stop the download, install the package, and resume the download.
* I'm installing lots of application from the Software Centre. While 1 app is installing the next should be downloading.
* Run apt-get from command while browsing software in Synaptic.

To avoid multiple instances of apt downloading the same file, each partial file should have it's own lock (For example, /var/cache/apt/archives/partial/inkscape_0.48.1-2ubuntu2_i386.deb would have inkscape_0.48.1-2ubuntu2_i386.lock). It may also be necessary to prevent updating package lists (sudo apt-get update) when any download lock exists as well as apt's main lock.