Section 2.3.1 is the C0 set, which "is not stored or displayed"
Section 2.3.2 is the C1 set, so interpret "all control characters"
in this context as meaning "all C1 characters".

This "feels" more like what the spec means.

This is the unicode replacement character, now displayed whenever
a G1 byte is received (byte values 160-255).

Prestel terminals are 7-bit devices, and use special escape
sequences to select alternate glyphs.  The Videotex standards
define a default G1 set though, which I am not supporting in the
1.x versions.  So that sysops and users know "something weird
happened", this weird glyph will clearly indicate that.

The C1 characters (128-159) I am supporting though simply because
it's easy to do, and I saw at least one BBS using them.  These BBSs
won't actually work with a real Prestel terminal though... they may
end up as parity errors, or they may end up as C0 bytes, or they
may be replaced with a '?'... I've seen all three now. SyncTERM can
at least do the right thing since it's well defined.

This may also fix held mosaic display for unhandled C0 bytes... it
looks like previously they were ignored, but the Prestel Terminal
Specification clearly states that "Generally all control characters
are displayed as spaces"... it doesn't limit them to supported
control characters.

At the same time, fix an old error in prestel_handle_escaped() that
didn't pass the ctrl to prestel_apply_ctrl_after() properly, and
always flush the print buffer before calling prestel_handle_escaped()

We still shouldn't actually get C1 characters on a Prestel connection,
but if we do, at least we're doing the right thing now.

As for G1 characters, the default repetoire for these terminals per
ITU-T REC. T0101 is the mosaic character set with smoothed moasics,
something there's no evidence of a Prestel terminal ever supporting.
In order to implement those properly, I would need special handling
of "separated" in the renderer, and would need to fiddle with the
font to include the contiguous smoothed mosaics (and exclide the
separated ones).  Since this would end up allowing wildly un-Pretel
behaviour (ie: mosaics without a mosaic escape) I'm inclined to
just treat them all as spaces and move on util/unless I do full
support for all the Videotex standards.  Nobody has asked me to
open this can of worms, so I'm just going to leave it on the shelf.

Blinking text is opposite of the cursor

For "PC" modes, cursor blinked at 1/16th of the VSYNC rate, so use
the CGA timings, where were generally the slowest of the bunch...
This means cursor blink at 3.745Hz, and character blink at 1.8725Hz.

For Prestel, character blink was 0.75Hz with a 3:1 On:Off ratio.
The cursor on the other hand was 1/32th the VSYNC and was generally
PAL, so 1.5625Hz.

I still need to dig into C64 and Atari modes, because they're likely
way off now (assuming either supports blinking).

Only 0-31 and 128-255 are left needing CP437 love.

Also hack together a 12x20 "CP437" font that's just the Prestel font
with the characters uifc32 uses from cp437 in it.

Update for v1.4

Move reveal/dirty status into background colour.
Should fix ticket 182.

No change in functionality, just code comprehension

If enabled, this option prevents logins to this service from changing the
protocol (aka modem) field for a user logging-in.

This is a work around for Deon who has some message areas set to require
"PROT NOT IMAP" for access requirements and when his IMAP client connects
and logs-in, that changes the protocol field in his user account (to "IMAP")
which means that user account cannot see/read those message areas (until the
protocol field is changed by another login to another server/service) and
thus won't receive echomail notifications for message received for them in
those areas.

Defeat the Windows getaddrinfo feature:
If the pNodeName parameter contains an empty string, all registered addresses on the local computer are returned.

at least for me, "fe80::5dfc:b29c:85d6:8de7%21"

at least, "vert.search.charter.net" in my case

This is just the ones mentioned in the jsdocs.  I'll add more
if/when I want them. :D

corresponding wth new user DELDATE field

alert() doesn't throw exception on null/undefined, just no arg

deny() throws exception on no args or null/undefined arg

So don't check for null/undefined argv[0] if not passed one

Hopefully this will fix the occasional crash in the testsuites
(and presumably, occasional crash in other things that use background
threads with js.exec(), if there are any).

Except this time, in the right place.

This reverts commit ed8c30da.

This reverts commit 7eb498aa.

Hopefully this will fix the occasional crash in the testsuites
(and presumably, occasional crash in other things that use background
threads with js.exec(), if there are any).