I applied the function GetCurrentChangeLog change in r63554. I guess the GetHostName stuff was little out of topic in this GetUserName thread.
If somebody knows about Amiga HostName, please tell me (PM, mail).
As already mentioned by others, Amiga did not had hardware to connect to a network by default.
As such the implementation of the network stack depended on the hardware vendor, although there were some standard/default stacks available.
AmiTCP, Miami and BSDSocket are just a few names in relation to that subject and which might be able to get you the hostname using an environment variable (when setup correctly) or can be obtained by a library function. MorphOS for instance can make use of yet another stack, while AROS (and Amiga's using AROS kickstart) attempts to provide BSDSocket by default.
The best solution to that imho would be to solve it just as
ApplicationName and
VendorName do it by providing a custom override for the enduser, such as
OnGetApplicationName and
OnGetVendorNameThat way you are able to provide a default implementation (depending on the platform), but at same time let the implementation details over to the end-user in case end-user environment requires it.
Would that be an option ?
edit, just noticed the first question
Question about Amiga: does it need special treatment? Does it have 'COMPUTERNAME'?
It does when that specific environment variable is set
(e.g., no it does not have that environment variable by default. I am not aware of any software that does supply this particular name).