gnupg depends on libusb?!

[dave@…]

pluto:~ dave% sudo port install gnupg
Warning: port definitions are more than two weeks old, consider using selfupdate
--->  Computing dependencies for gnupg
--->  Dependencies to be installed: libusb-compat libusb
--->  Fetching archive for libusb
--->  Fetching libusb
--->  Attempting to fetch libusb-1.0.8.tar.bz2 from http://voxel.dl.sourceforge.net/libusb
--->  Verifying checksum(s) for libusb
--->  Extracting libusb
--->  Configuring libusb
--->  Building libusb
--->  Staging libusb into destroot
--->  Packaging txz archive for libusb 1.0.8_0
--->  Installing libusb @1.0.8_0
--->  Activating libusb @1.0.8_0
--->  Cleaning libusb
--->  Fetching archive for libusb-compat
--->  Fetching libusb-compat
--->  Attempting to fetch libusb-compat-0.1.3.tar.bz2 from http://voxel.dl.sourceforge.net/libusb
--->  Verifying checksum(s) for libusb-compat
--->  Extracting libusb-compat
--->  Configuring libusb-compat
--->  Building libusb-compat
--->  Staging libusb-compat into destroot
--->  Packaging txz archive for libusb-compat 0.1.3_0
--->  Installing libusb-compat @0.1.3_0
--->  Activating libusb-compat @0.1.3_0
--->  Cleaning libusb-compat
--->  Fetching archive for gnupg
--->  Fetching gnupg
--->  Attempting to fetch gnupg-1.4.11.tar.bz2 from http://ykf.ca.distfiles.macports.org/MacPorts/mpdistfiles/gnupg
--->  Verifying checksum(s) for gnupg
--->  Extracting gnupg
--->  Configuring gnupg
--->  Building gnupg
--->  Staging gnupg into destroot
--->  Packaging txz archive for gnupg 1.4.11_0
--->  Installing gnupg @1.4.11_0
--->  Activating gnupg @1.4.11_0
--->  Cleaning gnupg

[ryandesign (Ryan Carsten Schmidt)]

Yes, the gnupg port depends on the libusb port, because the gpg program links with the libusb library.

$ otool -L /opt/local/bin/gpg
/opt/local/bin/gpg:
	/opt/local/lib/libiconv.2.dylib (compatibility version 8.0.0, current version 8.0.0)
	/opt/local/lib/libintl.8.dylib (compatibility version 10.0.0, current version 10.1.0)
	/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 125.2.0)
	/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation (compatibility version 150.0.0, current version 550.29.0)
	/opt/local/lib/libz.1.dylib (compatibility version 1.0.0, current version 1.2.5)
	/opt/local/lib/libbz2.1.0.dylib (compatibility version 1.0.0, current version 1.0.6)
	/opt/local/lib/libreadline.6.1.dylib (compatibility version 6.0.0, current version 6.1.0)
	/opt/local/lib/libusb-0.1.4.dylib (compatibility version 9.0.0, current version 9.4.0)

[dave@…]

But that's insane! What does encryption have to do with usb? Are you certain?

[blb@…]

It's needed to work with some smartcards.