which takes entries of the format <make-definition-name>=<pkgname>. This
has not been added to MAKEFLAGS because (a) premature optimisation is the
root of all evil, and (b) because the .for loop used to implement this
shows the wrong results when multiple prefices are evaluated.
Modify all the package Makefiles to use EVAL_PREFIX, thereby simplifying
them considerably.
ALso simplify the logic to calculate the prefix as well.
package's prefix would not work as part of the environment specification
via MAKE_ENV (as it would not be executed in the correct directory).
Fix this by invoking pkg_info(1) directly, not via an intermediate make(1)
step - this is not as clean, but more effective (i.e. it works).
a bit more user-friendly.
Introduce a show-{gtk+,imlib,kdebase,qt1,qt2,xpm}-prefix target in
bsd.pkg.mk, and use "${MAKE} show-*-prefix" in package Makefiles.
