some tools such as nm have no manpages on macOS
for example:
$ man nm
No manual entry for nm
but online manpage is available from Apple:
https://developer.apple.com/legacy/library/documentation/Darwin/Reference/ManPages/man1/nm.1.html
according to this page: https://developer.apple.com/legacy/library/documentation/Darwin/Reference/ManPages/#
indicate manual pages that are not installed by default in the client version of Mac OS X
But how to get these additional manpage installed?