Without `--root` or `--image`, the `security` command inspects all currently
loaded service units if no unit name is specified. But with `--root` or
`--image` with `--offline=true`, the `security` command exits silently if no
unit name is specified.
Also, fixed description of `--root` and `--image` in the man page, and added
missing `--unit` option to help text.
man:
- `verify` requires an argument
- `security` does not require an argument
- `fdstore` requires an argument
- `image-policy` requires an argument
`--help` text:
- missing `image-policy` command
- `cat-config` requires NAME or PATH
ExecStart= and friends for .service and .socket can be specified
multiple times.
This also checks all commands for .mount and .swap, not only for the
current control command.
The man page doesn't even mention errno. It just says that ferror() should
be used to check for errors. Those writes are unlikely to fail, but if they
do, errno might even be 0. Also, we have fflush_and_check() which does
additional paranoia around errno, because we apparently do not trust that
errno will always be set correctly.
If the requested unit is not in the current working directory, it is not
necessary to include the current working directory in SYSTEMD_UNIT_PATH.
Follow-up for 45519d13a4.
Fixes#30166.
