It really depends on the application that is used to open a document. perldoc uses application defined in PERLDOC_PAGER, MANPAGER, or PAGER environment variable.

It defaults to less viewer, so you should press q when browsing the document.

  But if by accident you press other keys, you might need to finish the operation before q would allow you to quit.

It really depends on the application that is used to open a document. perldoc uses application defined in PERLDOC_PAGER, MANPAGER, or PAGER environment variable.

It defaults to less viewer on most systems, so you should press q when browsing the document. But if by accident you pressed other keys, you might need to finish the operation before q would allow you to quit.

Wikipedia article on less has its keyboard shortcuts explained in detail.