By default installation, Ubuntu does not include the manual pages for developer, use the following command to install them manually:
1. apt-cache search manpages-dev
This command search the man pages and output the following:
manpages-dev - Manual pages about using GNU/Linux for developmentmanpages-de-dev - German development manpagesmanpages-fr-extra - French version of the manual pages2. sudo apt-get install manpages-dev
this command install the man pages in the computer.