Can any one explain me this script from rules/post/ptxd_make_image_common.make used while creating root.ubifs image

DOPERMISSIONS := '{     \
        if ($$1 == "f") \
                printf("chmod %s \".%s\"; chown %s.%s \".%s\";\n", $$5, $$2, $$3, $$4, $$2);    \
        if ($$1 == "n") \
                printf("rm -f \".%s\"; mkdir -p \".`dirname \"%s\"`\"; mknod -m %s \".%s\" %s %s %s; chown %s.%s \".%s\";\n", $$2, $$2, $$5, $$2, $$6, $$7, $$8, $$3, $$4, $$2);}'