Features:
+* maybe add support for binding and connecting AF_UNIX sockets in the file
+ system outside of the 108ch limit. When connecting, open O_PATH fd to socket
+ inode first, then connect to /proc/self/fd/XYZ. When binding, create symlink
+ to target dir in /tmp, and bind through it.
+
* tmpfiles: for f/F/w lines, if the argument columns is left unspecified, look
for a service credential named after the file path to write to, and load
contents to write from there. Usecase: provision arbitrary files from