Previously, .device units generated by SYSTEMD_ALIAS= udev properties
are not supported to specify devices for e.g. 'udevadm info'.
Before:
```
$ udevadm info sys-subsystem-net-devices-enp0s31f6.device
Unknown device "sys-subsystem-net-devices-enp0s31f6.device": No such device
```
After:
```
$ ./udevadm info sys-subsystem-net-devices-enp0s31f6.device
P: /devices/pci0000:00/0000:00:1f.6/net/enp0s31f6
L: 0
E: DEVPATH=/devices/pci0000:00/0000:00:1f.6/net/enp0s31f6
E: INTERFACE=enp0s31f6
E: IFINDEX=2
E: SUBSYSTEM=net
E: USEC_INITIALIZED=25317523
E: ID_NET_NAMING_SCHEME=v245
(snip)
```
This is convenient when working with device units in systemd. Instead of
converting the systemd unit name to a path to feed to udevadm, udevadm
info|trigger can be called directly on the unit name.
The man page is reworked a bit to describe the modern syntax with positional
arguments first. It's just simpler to use than the positional options.
$ git grep -e 'This program is free software' -l |grep -v LICENSE | \
xargs perl -i -0pe 's/ \* This program.*?for more details.\s*\*\n( \* You should have.*licenses.>.\n)?//gms'
For some reason they were missed previously. All those files seem to
have proper SDPX tags.
There are more than enough calls doing string manipulations to deserve
its own files, hence do something about it.
This patch also sorts the #include blocks of all files that needed to be
updated, according to the sorting suggestions from CODING_STYLE. Since
pretty much every file needs our string manipulation functions this
effectively means that most files have sorted #include blocks now.
Also touches a few unrelated include files.
After all it is now much more like strjoin() than strappend(). At the
same time, add support for NULL sentinels, even if they are normally not
necessary.
Yu Watanabe