Created attachment 754432 [details]
A proposed patch for solution 1 from comment #0

Description of problem:
If you want to test your new configuration file and you pass a relative file system path as the last argument of systemd-tmpfiles, systemd-tmpfiles prints the following message:
"Failed to open 'my_tmpfiles.conf', ignoring: No such file or directory"

The help text doesn't say that an absolute path is required.

$ systemd-tmpfiles --help
systemd-tmpfiles [OPTIONS...] [CONFIGURATION FILE...]

Creates, deletes and cleans up volatile and temporary files and directories.

  -h --help             Show this help
     --create           Create marked files/directories
     --clean            Clean up marked directories
     --remove           Remove marked files/directories
     --prefix=PATH      Only apply rules that apply to paths with the specified prefix

Version-Release number of selected component (if applicable):
systemd-204-2.el7.1.x86_64

Any one of these solutions would be fine:
1) if no standard tmpfiles directory contains the configuration file, systemd-tmpfiles tries to open the configuration file from the current directory.
2) more verbose help text 
3) more precise error message