Re: [MACTCL] "puts" and Console.app

[Daniel A. S. <st...@ma...>]

Kevin,

On 07/03/2007, at 14:24, Kevin Walzer wrote:

> Does anyone know if there is a way to get a Tcl/Tk application on the
> Mac to write output to Console.app? That is a standard tool to get  
> error
> messages from GUI applications. However, when I use "puts"  
> statements in
> my programs to check error messages, they don't show up in Console,  
> just
> in Terminal.

when an app is opened from the Finder (or more generally via  
LaunchServices), stdout and stderr are sent to the OS console (and  
stdin is /dev/null), but because TkAqua uses the Tk console window in  
that case and redirects the stdout/stderr channels to it, you cannot  
[puts] to them to output to the OS console (but note that e.g. fprintf 
(stderr) from the C level does go to the OS console).
However, you can [open] /dev/stdout or /dev/stderr from tcl to get  
access to the C level stdout and stderr (i.e. fd's 1 and 2), and  
[puts] to these will go to the console if Wish was started from  
Finder; or if you want to always output to the console, regardless of  
where the C stdout and stderr may have been redirected, you can open / 
dev/console from tcl:

% set c [open /dev/console WRONLY]
% fconfigure $c -buffering none
% puts $c test

Cheers,

Daniel

-- 
** Daniel A. Steffen        Dept. of Mathematics  **
** Macquarie University     NSW 2109 Australia    **