when I give this command
apt-get install build-essential autoconf automake libxmu-dev
it gives the following error
E: Package 'build-essential' has no installation candidate
E: Package 'autoconf' has no installation candidate
E: Package 'automake' has no installation candidate
E: Unable to locate package libxmu-dev
lsb_release -sr, 2)sudo apt-get update, 3)apt-cache policy build-essential, 4)grep -r ^deb /etc/apt/sources.list*. Please [edit] your question to do so and please use proper formatting. – gertvdijk Sep 15 '14 at 13:22