How do I get wireless working from the Debian shell?

Here is what worked for me on a C700:

  cru cardctl scheme CardResume
  cru cardclt scheme qpewlanX  # X is a number of 0 or more and corresponds to the numer of the WLAN connection defined in the ["QTopia"] Network GUI

To shut down the wireless connection, do the following:

  cru cardctl scheme CardSuspend

You can also turn the network on and off with these commands:

  cru ifconfig eth0 up
  cru ifconfig eth0 down