Hello,

I have a weird behaviour with tclsh in cygwin (mobaxterm) environment and I really doesn't know why so I'd really appreciate any clue.

Scenario:

I've installed magisplat in my windows 10 so I have tclsh available in my path.

When I open a cmd windows shell I can run tclsh and I get a tcl prompt (%) and command echo:

c\:> tclsh
%

% puts "hello"
hello

But when I invoke tclsh from a mobaxterm terminal window I get no prompt and a solid squared cursor ([]):

$ tclsh
[]
puts "hello"
hello
[]

It also seems there's no command echo:

$ tclsh
set h hello
set h
puts "$h"
hello
[]

where it should be:

$ tclsh
% set h hello
hello
% set h
hello
% puts "$h"
hello

Also it seems tclsh is treating paths as windows style:

$ tclsh
puts "[set auto_path]"
C:/Apps/Tcl86/lib/tcl8.6 C:/Apps/Tcl86/lib

when I expect it would use unix like paths

My assumption:

I think this weird behaviour may be related to the fact of using a windows program in a "unix" shell environment (cygwin mobaxterm), the tclsh program cygwin is using is the one installed by magicsplat:

$ which tclsh
/drives/c/Apps/Tcl86/bin/tclsh

And so there's a clash between naming conventions, if I create a tcl file just to require package ticklecharts like:

lappend auto_path "/home/mobaxterm/myDownloads/tcl/ticklecharts-master"
puts "[set auto_path]"
package require ticklecharts

and run it from ticklechars dir:

$ pwd
/home/mobaxterm/myDownloads/tcl/ticklecharts-master
$ tclsh ej.tcl
C:/Apps/Tcl86/lib/tcl8.6 C:/Apps/Tcl86/lib /home/mobaxterm/myDownloads/tcl/ticklecharts-master
can't find package ticklecharts
while executing
"package require ticklecharts"
(file "ej.tcl" line 5)

changing the path to add to auto_path in the file to different values I get:

- with /drives/c/Users/p/Downloads/tcl/ticklecharts-master
$ tclsh ej.tcl
C:/Apps/Tcl86/lib/tcl8.6 C:/Apps/Tcl86/lib /drives/c/Users/p/Downloads/tcl/ticklecharts-master
can't find package ticklecharts
while executing
"package require ticklecharts"
(file "ej.tcl" line 5)

- with current dir (.):
$ tclsh ej.tcl
C:/Apps/Tcl86/lib/tcl8.6 C:/Apps/Tcl86/lib .
html:.\render.html

- with current dir as windows style path:
$ tclsh ej.tcl
C:/Apps/Tcl86/lib/tcl8.6 C:/Apps/Tcl86/lib {C:\Users\p\Downloads\tcl\ticklecharts-master}
html:.\render.html

So it reckonizes windows style paths only

Maybe this is the reason of weird behaviour too, a kind of clash with internal paths or files o even pipes.

Probably the solution is to install tcl from cygwin itself, but I really don't understand why it behaves so weird.

Of course If I execute tclsh from cygwin through cmd.exe everything goes ok:

$ cmd.exe /c tclsh.exe
% set h hello
hello
% set h
hello

Any idea or explanation?

El domingo, 26 de marzo de 2023 a las 16:43:07 UTC+2, pd escribió:

> Any idea or explanation?

Of course this is just for fun, I'm be curious about this behaviour I cannot explain, please don't loose any time with this, just if you have a free time to waste ;-)

pd <eukelade@gmail.com> wrote:
> I think this weird behaviour may be related to the fact of using a
> windows program in a "unix" shell environment (cygwin mobaxterm), the
> tclsh program cygwin is using is the one installed by magicsplat:

It is. Windows is very different internally from Unix (even if MS
claims and/or got is certified as 'posix' compatible) and you will find
lots of little tidbits like this where square pegs just don't fit
properly into round holes. At the Tcl script level the Tcl runtime
papers over the differences so the script see's little of them. But at
the interface just outside the runtime to the rest of the environment
you are at the mercy of whatever is handling that (in your case the
cygwin runtime).

Another one that can be very irritating when one uses "puts stderr"
debugging sometimes is that pure GUI programs don't have a
stdin/stderr/stdout IO channel available.

On Sunday, March 26, 2023 at 8:39:53 AM UTC-7, Rich wrote:
> pd <euke...@gmail.com> wrote:
> > I think this weird behaviour may be related to the fact of using a
> > windows program in a "unix" shell environment (cygwin mobaxterm), the
> > tclsh program cygwin is using is the one installed by magicsplat:
> It is. Windows is very different internally from Unix (even if MS
> claims and/or got is certified as 'posix' compatible) and you will find
> lots of little tidbits like this where square pegs just don't fit
> properly into round holes. At the Tcl script level the Tcl runtime
> papers over the differences so the script see's little of them. But at
> the interface just outside the runtime to the rest of the environment
> you are at the mercy of whatever is handling that (in your case the
> cygwin runtime).
>
> Another one that can be very irritating when one uses "puts stderr"
> debugging sometimes is that pure GUI programs don't have a
> stdin/stderr/stdout IO channel available.

The specific problem here is the "isatty()" posix function. This function does not work correctly in a Windows Console. This function is only used when Tclsh is built for "unix". The Windows build does not use this function. Instead, tclsh is built as a Console Application which guarantees a Windows console is present, and tclsh operates accordingly.

Since the "unix" build uses isatty(), and this function always returns "false" on Windows, tclsh does not enable interactive mode, which disables the prompt. If you type in: set tcl_interactive 1, then the prompt will appear..

-Brian

Am 26.03.2023 um 16:43 schrieb pd:
> Hello,
>
> I have a weird behaviour with tclsh in cygwin (mobaxterm) environment and I really doesn't know why so I'd really appreciate any clue.
>
> Scenario:
>
> I've installed magisplat in my windows 10 so I have tclsh available in my path.
>
> When I open a cmd windows shell I can run tclsh and I get a tcl prompt (%) and command echo:
>
> c\:> tclsh
> %
>
> % puts "hello"
> hello
>
> But when I invoke tclsh from a mobaxterm terminal window I get no prompt and a solid squared cursor ([]):
>
> $ tclsh
> []
> puts "hello"
> hello
> []
>
> It also seems there's no command echo:
>
> $ tclsh
> set h hello
> set h
> puts "$h"
> hello
> []
>
> where it should be:
>
> $ tclsh
> % set h hello
> hello
> % set h
> hello
> % puts "$h"
> hello
>
> Also it seems tclsh is treating paths as windows style:
>
> $ tclsh
> puts "[set auto_path]"
> C:/Apps/Tcl86/lib/tcl8.6 C:/Apps/Tcl86/lib
>
> when I expect it would use unix like paths
>
> My assumption:
>
> I think this weird behaviour may be related to the fact of using a windows program in a "unix" shell environment (cygwin mobaxterm), the tclsh program cygwin is using is the one installed by magicsplat:
>
> $ which tclsh
> /drives/c/Apps/Tcl86/bin/tclsh
>
> And so there's a clash between naming conventions, if I create a tcl file just to require package ticklecharts like:
>
> lappend auto_path "/home/mobaxterm/myDownloads/tcl/ticklecharts-master"
> puts "[set auto_path]"
> package require ticklecharts
>
> and run it from ticklechars dir:
>
> $ pwd
> /home/mobaxterm/myDownloads/tcl/ticklecharts-master
> $ tclsh ej.tcl
> C:/Apps/Tcl86/lib/tcl8.6 C:/Apps/Tcl86/lib /home/mobaxterm/myDownloads/tcl/ticklecharts-master
> can't find package ticklecharts
> while executing
> "package require ticklecharts"
> (file "ej.tcl" line 5)
>
> changing the path to add to auto_path in the file to different values I get:
>
> - with /drives/c/Users/p/Downloads/tcl/ticklecharts-master
> $ tclsh ej.tcl
> C:/Apps/Tcl86/lib/tcl8.6 C:/Apps/Tcl86/lib /drives/c/Users/p/Downloads/tcl/ticklecharts-master
> can't find package ticklecharts
> while executing
> "package require ticklecharts"
> (file "ej.tcl" line 5)
>
> - with current dir (.):
> $ tclsh ej.tcl
> C:/Apps/Tcl86/lib/tcl8.6 C:/Apps/Tcl86/lib .
> html:.\render.html
>
> - with current dir as windows style path:
> $ tclsh ej.tcl
> C:/Apps/Tcl86/lib/tcl8.6 C:/Apps/Tcl86/lib {C:\Users\p\Downloads\tcl\ticklecharts-master}
> html:.\render.html
>
> So it reckonizes windows style paths only
>
> Maybe this is the reason of weird behaviour too, a kind of clash with internal paths or files o even pipes.
>
> Probably the solution is to install tcl from cygwin itself, but I really don't understand why it behaves so weird.
>
> Of course If I execute tclsh from cygwin through cmd.exe everything goes ok:
>
> $ cmd.exe /c tclsh.exe
> % set h hello
> hello
> % set h
> hello
>
>
> Any idea or explanation?

Are you aware, that tcl may also be build using cygwin?
Perhaps, there is also a tclsh package within the cygwin distribution (I
don't know).
Jan Nijtmans made a lot of effort to get tcl run on cygwin. I remember a
conference contribution at ETCL (in Strasbourg, I think).

Harald

Hello Brian,

I think you hit the point,

El lunes, 27 de marzo de 2023 a las 0:35:57 UTC+2, briang escribió:

> The specific problem here is the "isatty()" posix function. This function does not work correctly in a Windows Console. This function is only used when Tclsh is built for "unix". The Windows build does not use this function.. Instead, tclsh is built as a Console Application which guarantees a Windows console is present, and tclsh operates accordingly.
>
> Since the "unix" build uses isatty(), and this function always returns "false" on Windows, tclsh does not enable interactive mode, which disables the prompt. If you type in: set tcl_interactive 1, then the prompt will appear.

bingo!

$ tclsh
set h hello
[]
set tcl_interactive 1
1 % set h hello
hello
%

So I think the conservative solution is to include the line "set tcl_interactive 1" at the beginning of all my scripts so I can use both in mobaxterm shell and windows cmd shell, reasoning it wouldn't affect to windows version (I've tested it)

Thanks very much to bring peace to my brain ;-)

El lunes, 27 de marzo de 2023 a las 8:18:36 UTC+2, Harald Oehlmann escribió:

> Are you aware, that tcl may also be build using cygwin?

I'm pretty sure it can be build using cygwin because cygwin has packages to install tcl

> Perhaps, there is also a tclsh package within the cygwin distribution (I
> don't know).

yes there are a few packages:

$ apt-cyg find tcl
Trying to download file setup.ini
Updated setup.ini

Searching for installed packages matching tcl:

Searching for installable packages matching tcl:
mingw64-i686-tcl
mingw64-x86_64-tcl
octave-octclip
pidgin-tcl
ruby-tcltk
tcl
tcl-db
tcl-db4.8
tcl-devel
tcl-itcl
tcl-itcl-devel
tcl-itk
tcl-itk-devel
tcl-iwidgets
tcl-ming
tcl-solv
tcl-sqlite3
tcl-tcldot
tcl-tix
tcl-tk
tcl-tk-devel
tcl-togl
tcl-togl-devel
tcl-xapian
tcl-xapian-doc
tcl3270
tcltk
timidity++-tcltk
weechat-tcl

So, as I said previously, this problem should be solved just installed a cygwin package for tcl but I didn't install because I don't want to have two tcl systems installed (magicspalt and cygwin) maybe clashing each other and for sure duplicating space without needed. The problem was not so bad I coudn't live with it, it was just a weird problem and I really want to know the reason operating here, just for fun and knowing.

regards

On Sunday, March 26, 2023 at 5:39:53 PM UTC+2, Rich wrote:
> pd wrote:
> > I think this weird behaviour may be related to the fact of using a
> > windows program in a "unix" shell environment (cygwin mobaxterm), the
> > tclsh program cygwin is using is the one installed by magicsplat:
> It is. Windows is very different internally from Unix (even if MS
> claims and/or got is certified as 'posix' compatible) and you will find
> lots of little tidbits like this where square pegs just don't fit
> properly into round holes. At the Tcl script level the Tcl runtime
> papers over the differences so the script see's little of them. But at
> the interface just outside the runtime to the rest of the environment
> you are at the mercy of whatever is handling that (in your case the
> cygwin runtime).
>
> Another one that can be very irritating when one uses "puts stderr"
> debugging sometimes is that pure GUI programs don't have a
> stdin/stderr/stdout IO channel available.
Well, actually, you can get the standard channels to work in a "DOS-box" on WIndows. Try:
c:> tclsh
% package require Tk
[A wish toplevel window appears - at least on my screen]
8.6.8
% [type in commands or have [puts] display its results]

Regards,

Arjen

On Monday, March 27, 2023 at 1:29:20 PM UTC+2, pd wrote:
> El lunes, 27 de marzo de 2023 a las 8:18:36 UTC+2, Harald Oehlmann escribió:
>
> > Are you aware, that tcl may also be build using cygwin?
> I'm pretty sure it can be build using cygwin because cygwin has packages to install tcl
> > Perhaps, there is also a tclsh package within the cygwin distribution (I
> > don't know).
> yes there are a few packages:
>
> $ apt-cyg find tcl
> Trying to download file setup.ini
> Updated setup.ini
>
> Searching for installed packages matching tcl:
>
> Searching for installable packages matching tcl:
> mingw64-i686-tcl
> mingw64-x86_64-tcl
> octave-octclip
> pidgin-tcl
> ruby-tcltk
> tcl
> tcl-db
> tcl-db4.8
> tcl-devel
> tcl-itcl
> tcl-itcl-devel
> tcl-itk
> tcl-itk-devel
> tcl-iwidgets
> tcl-ming
> tcl-solv
> tcl-sqlite3
> tcl-tcldot
> tcl-tix
> tcl-tk
> tcl-tk-devel
> tcl-togl
> tcl-togl-devel
> tcl-xapian
> tcl-xapian-doc
> tcl3270
> tcltk
> timidity++-tcltk
> weechat-tcl
>
> So, as I said previously, this problem should be solved just installed a cygwin package for tcl but I didn't install because I don't want to have two tcl systems installed (magicspalt and cygwin) maybe clashing each other and for sure duplicating space without needed. The problem was not so bad I coudn't live with it, it was just a weird problem and I really want to know the reason operating here, just for fun and knowing.
>
> regards
I have seen this problem also with other programs under Cygwin. I think it is buffering the output to screen in an awkward way.

Regards,

Arjen