Solve the available problem of dpkg in Ubuntu

To solve the available problem of dpkg in Ubuntu, I recently started a pcDuino, so it's okay. I want to familiarize myself with the linux environment, build various things, and then expand the sensor to play with open-source hardware, suddenly encountered such a problem 1sub-process/usr/bin/dpkgreturned... to solve the available problem of dpkg in Ubuntu, I recently started a pcDuino, so it's okay. I want to familiarize myself with the linux environment, build various things, and then expand the sensor to play with open-source hardware, suddenly such a problem occurs: 1sub-process/usr/bin/dpkg returned an error code (2). then, Baidu and Google cannot solve it, finally, I wrote an article from the available of dpkg. according to the shell prompts, I found/var/lib/dpkg/available and cat it. I can't understand it. I can't help it. start from here, find the following information: 1 sudo dpkg -- clear-avail is a big sigh, so cp took a look at avalable, and then executed dpkg -- clear-avail and then cat there was nothing, apt-get update & apt-get upgrade passed smoothly.