How to Export a man page using Mac Terminal to a file

If you want to export a man (manual) page for a command into a file, then you can make use of the Mac Terminal and make use of the output redirection symbol along with the file name that you want to export the text of the man page.

Let's take a look at an easy example:

man whoami > whoami_man_page.txt

Let me cat this file to see its content.

% cat whoami_man_page.txt 

WHOAMI(1)                   General Commands Manual                  WHOAMI(1)

NAME
     whoami – display effective user id

SYNOPSIS
     whoami

DESCRIPTION
     The whoami utility has been obsoleted by the id(1) utility, and is
     equivalent to “id -un”.  The command “id -p” is suggested for normal
     interactive use.

     The whoami utility displays your effective user ID as a name.

EXIT STATUS
     The whoami utility exits 0 on success, and >0 if an error occurs.

SEE ALSO
     id(1)

macOS 13.4                       June 6, 1993                       macOS 13.4

If you want to append data to the same file for other man pages, instead of > make use of >>

Operator	Description	Example
>	Used to redirects the output of a command to a file.	man ls > man_ls.txt
>>	Used to appends the output of a command to the end of a file.	man ls >> man_pages.txt