Programmer 7500/MAX_PROGRAMMERS.iso/INFO/KA9QTCPP/NNTP4NOS.ZIP/NNTPDOC.TXT

Text File | 1990-05-15 | 5.5 KB | 121 lines

The new changes (as of May 12, 1990) are described next, followed by older
changes:

Newsgroup name adjustment
    Previously, newsgroups whose names contained characters that were not
    valid in DOS filenames would not get created.  I now map any character
    that is nonalphanumeric and not '-' into an underscore ('_').

Locking of nntp.dat history files
    Previously, it was possible for a session to open while another was still
    in progress; the result would be that two processes would be trying to
    update these files.  I've added appropriate mlock() and rmlock() calls to
    prevent this.  If nntp.dat is locked when I try to first read it, I close
    the session and try again later.  If it's locked when I try to update it,
    I simply don't update it; the next session to that server will get the
    old date in the NEWNEWS command, but the old message ids will be found in
    the history file and so not transferred.  If the history file is locked,
    I abort the session; this is not a great solution, but is better than the
    alternative.

Updating of nntp.dat changed
    Instead of overwriting it in place (which for reasons unknown didn't seem
    to work for me), I now recreate it.

Enhanced NNTP DIR command
    You can now give a second argument, which becomes the Newsdir directory.

Changed date stamp on 'From ' lines
    used to be mm/dd/yy hh:mm:ss, now it's just elapsed seconds since origin
    of GMT.  Make it both easier to parse and easier for expire to work with.

Buffers in getarticle() now malloc'd
    used to be on stack -- Phil pointed out it's better to mallocw() them,
    so I do.

The following describes my changes to Anders Klemets' NNTP client for
the KA9Q NOS package.  The changes described herein are as of May 6, 1990.
                              --Bernie Roehl
                                [e-mail]

NNTP TRACE command
    The syntax is the same as for SMTP TRACE.  There are four levels of
    detail that can be specified:
        0 - no tracing
        1 - only serious errors reported
        2 - same as 1, plus transient errors reported
        3 - same as 2, plus session progress reported
        4 - same as 3, plus actual received articles displayed
    Note that (1) is the default, and corresponds to the way things were
    in Klemets' original code.

More error messages
    I've added some error reporting (most of it subject to the nntp trace
    setting).

NNTP DIR command
    Allows you to set a spool directory other than the mail directory.
    Note that this is *not* the "Newsdir" directory (where history and
    nntp.dat are kept) but rather the spool directory where the articles
    themselves are kept.  The idea is that you could store articles on
    another drive.

Connection windows
    You can now specify a range of times at the end of an "nntp add" command,
    in the form "nntp add localserver 600 22:00-23:00", which would cause
    the nntp connections to be made only between 10 pm and 11 pm local
    time.  (NOTE: uses gettime() call, which is DOS-specific).

Site-specific newsgroups
    You can now override the "nntp groups" setting for specific servers.
    For example,
          nntp groups !rec.pets.gerbils
          nntp add myfeed 1800
          nntp add anotherfeed 7200 2:00-5:00 rec.pets.gerbils
    would take a full newsfeed from site "myfeed" every half-hour, but
    would not take rec.pets.gerbils.  The group rec.pets.gerbils is brought
    in from site "anotherfeed" every 2 hours, but only connecting between
    2 and 5 am local time.

Accumulating NNTP ADD commands
    Because additional information is now added on to NNTP, the commands
    can get quite long.  Therefore, "nntp add" commands now merge their
    values.  For example,
           nntp add myfeed 1800 rec.pets.gerbils,6:00-9:00,7:30-9:30
           nntp add myfeed 7200 comp.binaries.eniac
           nntp add myfeed 600
           nntp list
    will produce the following:
        myfeed        (595/600 7:30-9:30) rec.pets.gerbils,comp.binaries.eniac
    Note that the interval value *replaces* the previous one, as does the
    window setting; the groups accumulate (up to 512 bytes total).
    To reset the group list, "nntp drop" the entry and re-add it.

File Locking
    The mlock() and rmlock() functions within NOS are now used to lock the
    news files while they're being updated.  This is for use in conjunction
    with a (yet-to-be-written) news-expiry program.

Date/time stamp on 'From' lines
    'From' lines in the news files now have the date and time appended,
    in the form MM/DD/YY HH:MM:SS.  This for use with a (yet-to-be-written)
    news expiry program.  (Note: this is the *arrival* date of the article,
    not the date it was posted on!)

Increased stack space
    Even in the original nntpcli.c, the stack allocated was not really enough.
    I've bumped it to 3k (up from 1k) because of all the array[NNTPMAXLEN]'s
    in getarticle() and elsewhere.

Updating of nntp.dat only if the session is succesful
    Otherwise, we might lose articles.

That's about it.  Be sure to read Anders Klemets' original description,
in klemets.txt, and of course read through the code to see how it works :-)

If you have any questions about the code, send mail to me at
[e-mail], or to [e-mail].

I'm working on an expiry program (as time permits...), and am thinking about
how to implement posting (using IHAVE).  Will keep you posted.