in chapter 2.6 :
In answering this, two flags will serve you well: -d m and “-p 2”...
make -p 2
usage: make [-BeikNnqrstWwX]
[-C directory] [-D variable] [-d flags] [-f makefile]
[-I directory] [-J private] [-j max_jobs] [-m directory] [-T file]
[-V variable] [variable=value] [target ...]
This is FreeBSD 10.3R
This documentation is there for history and actually was removed. FreeBSD does not use pmake anymore but bmake.
But the man page of make and /usr/share/mk/bsd.README still reference this doc:
man of page:
This manual page is intended as a reference document only. For a more
thorough description of make and makefiles, please refer to PMake - A
See also make(1), mkdep(1), style.Makefile(5) and `PMake - A Tutorial', located in /usr/share/doc/psd/12.make.
I will open a PR for this.