Error: port activate failed: Registry error: No port of e installed.

[Michael_google gmail_Gersten]

>> 2. I could use Mac's Time Machine backup to restore my system to the
>> way it was the day before I installed Macports.
>
> IIRC Time Machine does not work very well with MacPorts as it is unable
> to backup hardlinks.

Wha?? I have hard links all over the place; Time Machine doesn't like them?

Need to check that. (Yea, I know, HFS doesn't actually support hard
links, they are a "graft-on")

Single user mode isn't that much of an advanced topic.

During boot up: Hold down (I forget which; try both) "S" or "Apple-S".
After your grey (gray?) screen with the apple logo, you'll switch to a
black-and-white text display; some initial debugging messages will be
displayed, and then you'll get a message that says something like
"To make changes to the system: fsck -fy / ; mount -o rw /"

Followed by a prompt.

At this point, every command you type is "sudo". You cannot make any
changes to the system unless you type in those commands. None of the
normal startup stuff has happened, so you can do postmortems on a
crashed system (/tmp will still be intact, for example, as will any
swapfiles; useful if not encrypted).

Type in those two commands, and you can then make any changes (such as
chmod, etc).

Remember, once you've typed in that second command, you're sudo --
double check your typing.
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