Thorsten Froehlich's furious key-hammering produced this:
>> I don't know if/how POV handles them, though.
> 
> Unlike in Windos, in Mac OS and Unix, links (or aliases) are completely
> transparent for applications.

Actually, all NT-based Windows versions support links for directories when using
NTFS.  Microsoft, of course, chose not to give any good support for them (or
allow links to files).  I think the only Windows NT release to actually make use
of NTFS links (which MS calls "junctions") are the Server releases.  These
junction points are transparent to applications as well, but as I said before,
cannot be made without third-party software (stupidly enough...).

-- 
/*^*/light_source{100*<-5,2,-5>2}#macro I(i,n)#while(strlen(i)>=n)#local A=asc(
substr(i,n,1));#local a=asc(substr(i,n+1,1));cylinder{<div(A,8)-12,mod(A,8)-4,4
><div(a,8)-12,mod(a,8)-4,4>,0.1pigment{rgb z}}#local n=n+2;#end#end I("ScUe[]"1
/*<*/)I("mkmtlttk"1)//@_$#!,:<"Thhis polysig brought to you by Ian Burgmyer :)"

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"Christopher James Huff" <cja### [at] earthlinknet> wrote in message
news:cja### [at] netplexaussieorg...

<snip>

What really annoys me about win95/98 shortcuts to directories (I can't remember
if this is fixed under 2k/xp), is that you can't navigate using them if you are
trying to save a file. Windows just assumes you want to overwrite the .lnk file,
rather than go to the directory or file it points to.

f-ups set.

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Thorsten Froehlich <tho### [at] trfde> wrote:
> Unlike in Windos, in Mac OS and Unix, links (or aliases) are completely
> transparent for applications.  Thus there is no difference between them.  Of
> course, links (or aliases) can break.

  Actually there are two types of links in Unix: Hard links and soft links.

  Hard links can't break. A hard link is basically a duplicate entry in the
file allocation table (ie. it looks like two different files, but they
actually point two the same physical data in the disk). The file pointed
by hard links is removed only when all hard links to it are deleted (that's
why a hard link can never break). This feature, however, imposes a limitation
on hard links: The file pointed by the hard link must be located in the
same partition as the link itself.
  A soft link is looser: It's not bound to the file it points, as the hard
link, and it can point to any file anywhere. A soft link is simply an entry
which contains a path to the file it points (which can be absolute or
relative). A soft link is basically the name of a file. If the file is
deleted, the soft link breaks (because the file pointed by the soft link
does not exist anymore).

  From the point of view of applications, they don't see any difference
between files, hard or soft links (unless the specifically ask the system
with a specialized system call).

  Links are extremely handy. For example there are many applications which
create their setting/cache/etc files in the home directory of the user.
I have a limited quota in my home directory here and thus it's very limited
what I can place there. However, I have plenty of space in the local HD of
my work computer (my home directory is located in a network drive). When
the directory of some program takes too much space, I simply move it to
the local HD and make a soft link in my home directory pointing to the
new location; the program does not notice anything and works perfectly
(but it now writes everything to the local HD instead of my home directory).

  I curse Windows every time I would need this handy feature there... :)

-- 
#macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
[1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
-1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -

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In article <3e672bb9@news.povray.org>, Warp <war### [at] tagpovrayorg> 
wrote:

>   Actually there are two types of links in Unix: Hard links and soft links.

An alias is a bit of both. You can move the target around or rename it 
and it stays attached, but if you delete the file, it breaks. If you 
replace it with another file with the same name, the alias directs to 
the new file.
Hard and soft links are supported as usual, but you can't create them 
from the Finder.


>   From the point of view of applications, they don't see any difference
> between files, hard or soft links (unless the specifically ask the system
> with a specialized system call).

I don't know if aliases are implemented like this. An attempt to open an 
alias with the standard C code may attempt to open the actual alias 
file, not its target. To properly written Mac programs they behave like 
the target itself would, though.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: chr### [at] tagpovrayorg
http://tag.povray.org/

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Christopher James Huff <cja### [at] earthlinknet> wrote:
> I don't know if aliases are implemented like this. An attempt to open an 
> alias with the standard C code may attempt to open the actual alias 
> file, not its target.

  That would diminish the usefulness of aliases a lot.

-- 
#macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
[1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
-1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -

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In article <3e67773b@news.povray.org>, Warp <war### [at] tagpovrayorg> 
wrote:

> > I don't know if aliases are implemented like this. An attempt to open an 
> > alias with the standard C code may attempt to open the actual alias 
> > file, not its target.

Well, the command line tools don't recognize them, so I guess this is 
the case.


>   That would diminish the usefulness of aliases a lot.

Not really, almost everything uses higher level API's. The standard Unix 
tools don't, but that's about it.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: chr### [at] tagpovrayorg
http://tag.povray.org/

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In article <3e66b61e$1@news.povray.org> , "Ian J. Burgmyer" 
<the### [at] maccom> wrote:

> NTFS.

I know that NTFS supports them. It had to so M$ could claim Posix
compliance.  Of course, having a less-buggy Posix layer would have been
really helpful...

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org

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In article <3e672bb9@news.povray.org> , Warp <war### [at] tagpovrayorg>  wrote:

>   From the point of view of applications, they don't see any difference
> between files, hard or soft links (unless the specifically ask the system
> with a specialized system call).

Of course not.  After all, otherwise they would be useless.  Which is pretty
much what they are in Windos unless you want to start applications from your
desktop or the Start mess.

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org

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In article <cja### [at] netplexaussieorg> , 
Christopher James Huff <cja### [at] earthlinknet>  wrote:

>>   From the point of view of applications, they don't see any difference
>> between files, hard or soft links (unless the specifically ask the system
>> with a specialized system call).
>
> I don't know if aliases are implemented like this. An attempt to open an
> alias with the standard C code may attempt to open the actual alias
> file, not its target. To properly written Mac programs they behave like
> the target itself would, though.

Only from the Unix layer in Mac OS X (which end-user applications aren't
supposed to use).  For it an alias file cannot be seen because alias data is
stored in the resource fork.  The solution is not to use gcc but a
professional compiler with a reasonable runtime and C library, which on Mac
OS X means CodeWarrior (for C and C++ programs).

    Thorsten

____________________________________________________
Thorsten Froehlich, Duisburg, Germany
e-mail: tho### [at] trfde

Visit POV-Ray on the web: http://mac.povray.org

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Thorsten Froehlich's furious key-hammering produced this:
>> NTFS.
> 
> I know that NTFS supports them. It had to so M$ could claim Posix
> compliance.

Basically, yes.  Microsoft seems to have dumped POSIX compliance (it's not in
either XP release).  I'm not sure if it will be included in .NET Server 2003 but
I highly doubt it.

I could personally care less.  I'd rather have cygwin anyway. :)

Follow-ups set to povray.off-topic.

-- 
/*^*/light_source{100*<-5,2,-5>2}#macro I(i,n)#while(strlen(i)>=n)#local A=asc(
substr(i,n,1));#local a=asc(substr(i,n+1,1));cylinder{<div(A,8)-12,mod(A,8)-4,4
><div(a,8)-12,mod(a,8)-4,4>,0.1pigment{rgb z}}#local n=n+2;#end#end I("ScUe[]"1
/*<*/)I("mkmtlttk"1)//@_$#!,:<"Thhis polysig brought to you by Ian Burgmyer :)"

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