/usr/lib/x86_64-linux-gnu/pkgconfig/libusb.pc is in libusb-dev 2:0.1.12-20.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 | prefix=/usr
exec_prefix=${prefix}
libdir=/usr/lib/x86_64-linux-gnu
includedir=${prefix}/include
Name: libusb
Description: USB access library
Version: 0.1.12
Libs: -L${libdir} -lusb
Cflags: -I${includedir}
|