* guix/utils.scm (%struct-flock, F_SETLKW, F_SETLK, F_xxLCK) (fcntl-flock): Move to... * guix/build/syscalls.scm: ... here. New variables. * guix/nar.scm: Adjust imports accordingly. * tests/utils.scm ("fcntl-flock wait", "fcntl-flock non-blocking"): Move to... * tests/syscalls.scm: ... here. New tests. (temp-file): New variable.