port install -f <port> does not force copying or rebuilding of package

[nelson.ferreira@…]

neumann:~ root# port -d install libpng
DEBUG: Changing to port directory: /opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/graphics/libpng
DEBUG: OS darwin/11.2.0 (Mac OS X 10.7) arch i386
DEBUG: org.macports.load registered provides 'load', a pre-existing procedure. Target override will not be provided
DEBUG: org.macports.unload registered provides 'unload', a pre-existing procedure. Target override will not be provided
DEBUG: org.macports.distfiles registered provides 'distfiles', a pre-existing procedure. Target override will not be provided
DEBUG: Using group file /opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/_resources/port1.0/group/archcheck-1.0.tcl
DEBUG: adding the default universal variant
DEBUG: Reading variant descriptions from /opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/_resources/port1.0/variant_descriptions.conf
DEBUG: Attempting ln -sf /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_graphics_libpng/libpng/work /opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/graphics/libpng/work
DEBUG: changing euid/egid - current euid: 0 - current egid: 0
DEBUG: egid changed to: 501
DEBUG: euid changed to: 502
DEBUG: Starting logging for libpng
--->  Computing dependencies for libpng
DEBUG: Searching for dependency: zlib
DEBUG: Found Dependency: receipt exists for zlib
DEBUG: Skipping activate (libpng @1.4.8_0) since this port is already active
DEBUG: Executing org.macports.main (libpng)
DEBUG: clean phase started at Thu Dec 15 22:15:47 EST 2011
--->  Cleaning libpng
DEBUG: Executing org.macports.clean (libpng)
--->  Removing work directory for libpng
DEBUG: Removing directory: /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_graphics_libpng/libpng
DEBUG: delete: /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_graphics_libpng/libpng
DEBUG: No work directory found to remove at /var/root/.macports/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_graphics_libpng/libpng
DEBUG: Removing symlink: /opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/graphics/libpng/work
DEBUG: delete: /opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/graphics/libpng/work
DEBUG: Removing directory: /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_graphics_libpng/libpng
DEBUG: delete: /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_graphics_libpng/libpng

neumann:~ root# port -d install -f libpng
DEBUG: Changing to port directory: /opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/graphics/libpng
DEBUG: OS darwin/11.2.0 (Mac OS X 10.7) arch i386
DEBUG: org.macports.load registered provides 'load', a pre-existing procedure. Target override will not be provided
DEBUG: org.macports.unload registered provides 'unload', a pre-existing procedure. Target override will not be provided
DEBUG: org.macports.distfiles registered provides 'distfiles', a pre-existing procedure. Target override will not be provided
DEBUG: Using group file /opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/_resources/port1.0/group/archcheck-1.0.tcl
DEBUG: adding the default universal variant
DEBUG: Reading variant descriptions from /opt/local/var/macports/sources/rsync.macports.org/release/tarballs/ports/_resources/port1.0/variant_descriptions.conf
DEBUG: Starting logging for libpng
--->  Computing dependencies for libpng
DEBUG: Searching for dependency: zlib
DEBUG: Found Dependency: receipt exists for zlib
DEBUG: Skipping activate (libpng @1.4.8_0) since this port is already active
DEBUG: Executing org.macports.main (libpng)
DEBUG: clean phase started at Thu Dec 15 22:15:58 EST 2011
--->  Cleaning libpng
DEBUG: Executing org.macports.clean (libpng)
--->  Removing work directory for libpng
DEBUG: No work directory found to remove at /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_graphics_libpng/libpng
DEBUG: No work directory found to remove at /var/root/.macports/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_graphics_libpng/libpng
DEBUG: Removing directory: /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_graphics_libpng/libpng
DEBUG: delete: /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_graphics_libpng/libpng

[ryandesign@…]

Please use WikiFormatting.

The -f flag (and all other single-letter flags) has no effect unless placed immediately after the word port.

To forcibly upgrade a port, do the following:

sudo port -n upgrade --force libpng

If you want to ensure that you build from source and don't get a pre-built binary from our server, use:

sudo port -ns upgrade --force libpng

[nelson.ferreira@…]

And where are the long format flags accept for the commands documented exactly ? Because man port only lists the single letter flags

SYNOPSIS
     port [-bcdfknopqRstuvy] [-D portdir] [-F cmdfile] [action] [actionflags]
          [[portname | pseudo-portname | port-url]] [[@version] [+/-variant ...] ... [option=value ...]]

...

   install
     Install and activate portname.

The only mention at all, and en-passant of —force is in the upgrade action

and port help install says:

 port help install
Usage: install

Installs the given ports

This is at the very least a documentation bug IMO

[ryandesign@…]

short-form flags are global to port.

long-form flags are specific to the verb you're using.

"port help upgrade" for example explains what the --force flag does for the upgrade verb.