[Cialug] Having a "this should work" moment

[Zachary Kotlarek]

On Oct 1, 2009, at 8:58 PM, Josh More wrote:

> The three streams are:
>
> 0) Standard Input
> 1) Standard Output
> 2) Standard Error


You can get additional descriptors if you do:
	exec 3>&1
or:
	exec 4<&0

And you can close descriptors with:
	1>&-
or:
	0<&-
if you've created extra descriptors or want to force one of the  
standard ones to close.


Such tricks are occasionally handy if you're trying to see stdout  
while piping stderr, or if you need to trick a program into thinking  
that stdin is not available.

You can also redirect all stderr output to stdout for all the commands  
in a shell script by adding the line:
	exec 2>&1
to the top instead of adding 2>&1 to the end of each command.  
Similarly you could add:
	exec 1>>/var/log/script.out
and get all the output in a file, again without adding the redirect to  
each command.

	Zach

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