lib64expat1-dev software package provides XML parsing C library - development kit (64bit), you can install in your Ubuntu 12.04 LTS (Precise Pangolin) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install lib64expat1-dev
lib64expat1-dev is installed in your system.
Make ensure the lib64expat1-dev package were installed using the commands given below,
$ sudo dpkg-query -l | grep lib64expat1-dev *
You will get with lib64expat1-dev package name, version, architecture and description in a table
| Distro | Ubuntu 12 04 lts precise pangolin |
| Section | Library development |
| Package | lib64expat1-dev |
| Version | 2.0.1-7.2ubuntu1.4 [i386], 2.0 |
| Description | XML parsing C library - development kit (64bit) |
| Sub Section | libdevel |