By default Ubuntu doesn’t install the manual pages used for Linux software development which is an invaluable reference for any system developer. These man pages describe the Linux programming interface including Linux system calls as well as system library calls.
To install these man pages simply install the manpages-dev package.
$ sudo apt-get install manpages-dev
You can also install the POSIX specific interfaces by installing the manpages-posix-dev package.
$ sudo apt-get install manpages-posix-dev