Allow registration as a URL handler for FTP, SFTP

[karnesky]

Optional) registration as the default URL handler in
windows may be added with a registry addition similar to:

--BEGIN--
REGEDIT4

[HKEY_CLASSES_ROOT\sftp]
@="URL:sftp Protocol"
"URL Protocol"=""

[HKEY_CLASSES_ROOT\sftp\shell]

[HKEY_CLASSES_ROOT\sftp\shell\open]

[HKEY_CLASSES_ROOT\sftp\shell\open\command]
@="\"C:
Program Files
FileZilla
FileZilla.exe\" \"%1\""
--END--

Allowing FZ to register itself for FTP and SFTP URLs
would be useful.

For SFTP, this is potentially blocked by this bug:
​http://sourceforge.net/tracker/index.php?func=detail&aid=1454179&group_id=21558&atid=372241

[Alexander Schuch]

Another example is given in closed duplicate #4223.

[Alexander Schuch]

"Could we register FileZilla as a URL handler for FTP, SFTP, and FTPES hyperlinks" -- #9833

[Daniel Beardsmore]

Note that modern Windows versions (7 upwards, possibly Vista upwards) expect a more Mac-style registration to give the user proper choice. You would no longer write or overwrite the following, which is bad practice as it robs users of choice:

[HKEY_CLASSES_ROOT\sftp]

The URL launch definition would still be defined, e.g.

[HKEY_LOCAL_MACHINE\SOFTWARE\CLASSES\FileZilla.FTP]
; Same as HKCR; define the URL association here

Register FilezZilla as a program that can open files or URLs:

[HKEY_LOCAL_MACHINE\SOFTWARE\RegisteredApplications]
"FileZilla"="SOFTWARE
FileZilla 3
Capabilities"

Then, report what FileZilla is capable of:

[HKEY_LOCAL_MACHINE\SOFTWARE\FileZilla 3\Capabilities]
; Describe the program using the values that go here

[HKEY_LOCAL_MACHINE\SOFTWARE\FileZilla 3\Capabilities\URLAssociations]
; Define the associations from HKEY_LOCAL_MACHINE\SOFTWARE\CLASSES here, e.g.
"FTP"="FileZilla.FTP"

Windows will read this automatically as required and permit the user to choose a suitable application.

I notice that clients generally write their capability data under HKEY_LOCAL_MACHINE\SOFTWARE\Clients, inside subcategories like Mail (Hotmail, Outlook, Thunderbird) and StartMenuInternet (Firefox, Opera, Internet Explorer), e.g. Firefox has:

[HKEY_LOCAL_MACHINE\SOFTWARE\Clients\StartMenuInternet\Firefox-308046B0AF4A39CB\Capabilities\URLAssociations]
"ftp"="FirefoxURL-308046B0AF4A39CB"

A little bit more investigation is needed to be sure of what needs to be set. It’s just a matter of understanding quite what the correct practice is here, but it’s nothing too complicated from what I understand.