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can someone please explain this? i just downloaded MANIFEST.bz2 from
<ftp://ftp.slackware.no/pub/linux/slackware/slackware-9.1/slackware/>.
when the save-as dialog pops up, i rename the file to MANIFEST-9.1.bz2,
because i also have 9.0's MANIFEST.bz2 on the disk (called
MANIFEST-9.0.bz2).

after downloading, i do 'less MANIFEST-9.1.bz2'. great surprise, i get only
garbage. 'tar tjf MANIFEST-9.1.bz2' gives me the following errors:

tar: Dit ziet er niet uit als een tar archief
tar: Overslaan tot volgende kopregel
tar: Archive contains obsolescent base-64 headers
tar: Fout afsluiting uitgesteld na eerdere fouten

the first two and last errors are in dutch, they mean something like 'this
does not look like a tar archive', 'skipping to next header line' and
'Error exit postponed after previous errors'. (yeah, it's as meaningless in
dutch as it is in english...)

so i redownload the file, now keeping the name MANIFEST.bz2. i try 'less
MANIFEST,bz2' and everything works. so i rename the file to
MANIFEST-9.1.bz2, thinking the download must've been screwed.

but.

i do 'less MANIFEST-9.1.bz2' and *again* i get garbage!! 'tar tjf' gives
the same errors.

so i rename the file back to MANIFEST.bz2, and everything works fine again!

even more surprisingly (or not, perhaps): i can run 'bunzip2
MANIFEST-9.1.bz2' just fine. the file is decompressed without problems.

HOW IS THIS POSSIBLE???!!! and what on earth is going on??!!

btw, no problems with MANIFEST-9.0.bz2...

--
Joost Kremers joostkremers@yahoo.com
since when is vi an editor? a discussion on vi belongs in
comp.tools.unusable or something... ;-)

On 2 Dec 2003 02:14:04 GMT,
Joost Kremers <joostkremers@yahoo.com> wrote:
>
....
>
> i do 'less MANIFEST-9.1.bz2' and *again* i get garbage!! 'tar tjf' gives
> the same errors.
>
> so i rename the file back to MANIFEST.bz2, and everything works fine again!
....
> HOW IS THIS POSSIBLE???!!! and what on earth is going on??!!
>
> btw, no problems with MANIFEST-9.0.bz2...

Looking at /usr/bin/lesspipe.sh, which is defined in $LESSOPEN, it seems
a *.1.bz2 file is treated as compressed *roff source. I think this is
the course of your problem. Here are the offending lines:

#v+
*.1.bz2|*.2.bz2|*.3.bz2|*.4.bz2|*.5.bz2|*.6.bz2|*. 7.bz2|*.8.bz2|*.9.bz2|*.n.bz2|*.man.bz2)
# compressed *roff src?
if bzip2 -dc "$1" | file - | grep roff 1> /dev/null ; then
bzip2 -dc "$1" | nroff -S -mandoc -
fi ;;
#v-

This is how a normal *.bz2 file is treated:
#v+
*.bz2) bzip2 -dc "$1" 2>/dev/null ;;
#v-

HTH.


--
Mark Hill <usenet@mark.ukfsn.org> (Yahoo address not read)
GPG KeyID: 4A3B58AC

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On 2 Dec 2003 02:14:04 GMT, Joost Kremers <joostkremers@yahoo.com> wrote:
> after downloading, i do 'less MANIFEST-9.1.bz2'. great surprise, i get only
> garbage. 'tar tjf MANIFEST-9.1.bz2' gives me the following errors:

Errrmmmm... pardon me if I'm totally wrong here, but isn't less for
reading plaintext files? Then you use zless for reading gzip'd files,
and bzless[1] for reading bz2'd files. Or have I been wasting my time
with these additional utilities?

> the first two and last errors are in dutch, they mean something like 'this
> does not look like a tar archive', 'skipping to next header line' and
> 'Error exit postponed after previous errors'. (yeah, it's as meaningless in
> dutch as it is in english...)

Errrrmmmm... maybe I'm mistaken again, but I really don't think MANIFEST
is a tar file. bunzip2 MANIFEST-9.1.bz2 might do the trick for ya. Why
play with tar if there's no tarring involved? It's just a single file,
right?

I don't know what the switches you used above mean on tar, though, I
just know enough tar to know where to look in the man page or --help
output. :-)

> so i redownload the file, now keeping the name MANIFEST.bz2. i try 'less
> MANIFEST,bz2' and everything works. so i rename the file to
> MANIFEST-9.1.bz2, thinking the download must've been screwed.

Looks like somebody else answered why that worked. I'm surprised less
reads bz2'd files like that.

Craziness. :-)

[1] - bzless available upon request, I have a version grabbed from
Debian.

--
Rob | If not safe,
Email and Jabber: | one can never be free.
athlonrob at axpr dot net |
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On 2003-12-02, AthlonRob <junkmail@axpr.net> wrote:
>
> Errrmmmm... pardon me if I'm totally wrong here, but isn't less for
> reading plaintext files? Then you use zless for reading gzip'd files,
> and bzless[1] for reading bz2'd files. Or have I been wasting my time
> with these additional utilities?

If you have it, read /usr/bin/lesspipe.sh.

> Errrrmmmm... maybe I'm mistaken again, but I really don't think MANIFEST
> is a tar file. bunzip2 MANIFEST-9.1.bz2 might do the trick for ya.

MANIFEST*.bz2 are all bzip'd text files, not tar files, but bunzip2'ing
it will make for quite a large file. Better to bunzip2 -dc and pipe
the output through less (which is exactly what lesspipe.sh does).

- --keith

- --
kkeller-usenet@wombat.san-francisco.ca.us
(try just my userid to email me)
AOLSFAQ=http://wombat.san-francisco.ca.us/cgi-bin/fom

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On Mon, 1 Dec 2003 20:35:51 -0800, Keith Keller <kkeller-usenet@wombat.san-francisco.ca.us> wrote:
> If you have it, read /usr/bin/lesspipe.sh.

Cool - we should write one that calls file to properly identify a file
rather than guessing from it's extension - that's so M$-ish. :-)

:::adding it to his list of things he wants to think about doing:::

--
Rob | If not safe,
Email and Jabber: | one can never be free.
athlonrob at axpr dot net |
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AthlonRob wrote:
> Errrmmmm... pardon me if I'm totally wrong here, but isn't less for
> reading plaintext files? Then you use zless for reading gzip'd files,
> and bzless[1] for reading bz2'd files. Or have I been wasting my time
> with these additional utilities?

seems like you have. less works just as well on gzipped files and bzipped
files, *and* on tar files that are (b|g)zipped. i've never tried it on an
unzipped tar file, but i'm guessing that works too.

> Errrrmmmm... maybe I'm mistaken again, but I really don't think MANIFEST
> is a tar file.

aaarrgh! how stupid is that! you're right of course.

> Looks like somebody else answered why that worked. I'm surprised less
> reads bz2'd files like that.

it does, and it's very useful indeed...

and thanks to you, mark, for clarifying this issue to me.

--
Joost Kremers joostkremers@yahoo.com
Slackware doesn't have any quirks. Other distros have quirks. Slackware's
just pure Linux.