octave-dev

[OctDev] isunix() returns 1 under cygwin

[Etienne G. <et...@cs...>]

  Hi All,

since

octave:8> help isunix
isunix is the user-defined function from the file
/home=E6tienne/prog=F8ctave=F8ctave-forge=F8ctave-forge/main/general/isun=
ix.m

Always returns true.  If you are on a windows machine, be sure to
put an isunix.m which always returns false in your path.

and isunix returns 1 under the octave-2.1.50 cygwin package, am I
right to conclude that every user of that package who wants isunix to
answer correctly should modify that function?

  TIA,
=20
  Etienne

--=20
Etienne Grossmann ------ http://www.cs.uky.edu/~etienne

Re: [OctDev] isunix() returns 1 under cygwin

[Andy A. <ad...@nc...>]

On 12/26/05, Etienne Grossmann <et...@cs...> wrote:
> octave:8> help isunix
> isunix is the user-defined function from the file
> /home=E6tienne/prog=F8ctave=F8ctave-forge=F8ctave-forge/main/general/isun=
ix.m
>
> Always returns true.  If you are on a windows machine, be sure to
> put an isunix.m which always returns false in your path.

The semantics of 'isunix' depends on what you mean by UNIX.
Strictly speaking, only certain well defined OSes are UNIX. Linux,
for example, is not.

On the other hand, maybe UNIX means OSes that behave like
UNIX in most ways. cygwin has UNIX process semantics
(ie. fork) and file semantics (symlinks, select on files, etc.)

So, is cygwin UNIX? Clearly, a mingwin octave is not unix.

Maybe isunix should make a specific test.

--
Andy

Re: [OctDev] isunix() returns 1 under cygwin

[William P. Y. H. <wil...@gm...>]

On 12/27/05, Andy Adler <ad...@nc...> wrote:
> The semantics of 'isunix' depends on what you mean by UNIX.
> Strictly speaking, only certain well defined OSes are UNIX. Linux,
> for example, is not.
>
> On the other hand, maybe UNIX means OSes that behave like
> UNIX in most ways. cygwin has UNIX process semantics
> (ie. fork) and file semantics (symlinks, select on files, etc.)
>
> So, is cygwin UNIX? Clearly, a mingwin octave is not unix.
>
> Maybe isunix should make a specific test.
>

In Octave 2.9.4, isunix() is implemented as

function retval =3D isunix ()

  if (nargin =3D=3D 0)
    retval =3D octave_config_info ("unix");
  else
    usage ("isunix ()");
  endif

endfunction

AFAIK, it returns 1 on Cygwin (I know this by reading the sources, so
I'm not very sure)

Re: [OctDev] isunix() returns 1 under cygwin

[Etienne G. <et...@cs...>]

  Hi Andy,

thx for the answer. I should have added that I want to use isunix() to
determine whether I want to execute a (linux) binary called (say)
'foo' or a windows binary called 'fooWin.exe'. So I really want isunix
to return true iff it's Linux - my code will fail on other nixes but
that's ok for now.

  Cheers,

  Etienne

ps: More in detail on what I'm doing, I'm patching David Lowe's SIFT
    [1] image feature detector code for Matlab so that it'll run both
    on Matlab and Octave. His code runs both on Win and Linux.

[1] David G. Lowe, "Distinctive image features from scale-invariant
    keypoints,"International Journal of Computer Vision, 60, 2 (2004),
    pp. 91-110.

   http://www.cs.ubc.ca/~lowe/keypoints/



On Mon, Dec 26, 2005 at 05:16:15PM -0500, Andy Adler wrote:
# On 12/26/05, Etienne Grossmann <et...@cs...> wrote:
# > octave:8> help isunix
# > isunix is the user-defined function from the file
# > /home=E6tienne/prog=F8ctave=F8ctave-forge=F8ctave-forge/main/general/=
isunix.m
# >
# > Always returns true.  If you are on a windows machine, be sure to
# > put an isunix.m which always returns false in your path.
#=20
# The semantics of 'isunix' depends on what you mean by UNIX.
# Strictly speaking, only certain well defined OSes are UNIX. Linux,
# for example, is not.
#=20
# On the other hand, maybe UNIX means OSes that behave like
# UNIX in most ways. cygwin has UNIX process semantics
# (ie. fork) and file semantics (symlinks, select on files, etc.)
#=20
# So, is cygwin UNIX? Clearly, a mingwin octave is not unix.
#=20
# Maybe isunix should make a specific test.
#=20
# --
# Andy
#=20

--=20
Etienne Grossmann ------ http://www.cs.uky.edu/~etienne

Re: [OctDev] isunix() returns 1 under cygwin

[Bill D. <de...@se...>]

One thing that I could see as a good option for this would be for isunix=20
to have variable output arguements.  Perhaps something like [true/false,=20
osname, osversion, distro, distroversion].

Bill

On Mon, 26 Dec 2005, Etienne Grossmann wrote:

>
>  Hi Andy,
>
> thx for the answer. I should have added that I want to use isunix() to
> determine whether I want to execute a (linux) binary called (say)
> 'foo' or a windows binary called 'fooWin.exe'. So I really want isunix
> to return true iff it's Linux - my code will fail on other nixes but
> that's ok for now.
>
>  Cheers,
>
>  Etienne
>
> ps: More in detail on what I'm doing, I'm patching David Lowe's SIFT
>    [1] image feature detector code for Matlab so that it'll run both
>    on Matlab and Octave. His code runs both on Win and Linux.
>
> [1] David G. Lowe, "Distinctive image features from scale-invariant
>    keypoints,"International Journal of Computer Vision, 60, 2 (2004),
>    pp. 91-110.
>
>   http://www.cs.ubc.ca/~lowe/keypoints/
>
>
>
> On Mon, Dec 26, 2005 at 05:16:15PM -0500, Andy Adler wrote:
> # On 12/26/05, Etienne Grossmann <et...@cs...> wrote:
> # > octave:8> help isunix
> # > isunix is the user-defined function from the file
> # > /home=E6tienne/prog=F8ctave=F8ctave-forge=F8ctave-forge/main/general/=
isunix.m
> # >
> # > Always returns true.  If you are on a windows machine, be sure to
> # > put an isunix.m which always returns false in your path.
> #
> # The semantics of 'isunix' depends on what you mean by UNIX.
> # Strictly speaking, only certain well defined OSes are UNIX. Linux,
> # for example, is not.
> #
> # On the other hand, maybe UNIX means OSes that behave like
> # UNIX in most ways. cygwin has UNIX process semantics
> # (ie. fork) and file semantics (symlinks, select on files, etc.)
> #
> # So, is cygwin UNIX? Clearly, a mingwin octave is not unix.
> #
> # Maybe isunix should make a specific test.
> #
> # --
> # Andy
> #
>
> --=20
> Etienne Grossmann ------ http://www.cs.uky.edu/~etienne
>
>
>
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--=20
If you make a mistake you right it
immediately to the best of your ability.
   -- /usr/bin/fortune