[TriLUG] bash question

Joseph Mack NA3T jmack at wm7d.net
Wed Oct 17 20:42:13 EDT 2007


On Thu, 18 Oct 2007, Jeremy Portzer wrote:

> You can also use "eval"
>
> CMDA="ls |"
> CMDB="wc -l"
> eval "$CMDA$CMDB"

hmm. I see.

I had tried

eval `$CMDA$CMDB`

and got the error mentioned in my original post. I didn't 
think of eval'ing a string. I don't understand eval and try 
to avoid it, but have got a few other eval commands to work, 
so thought I understood it well enough for the moment. Well 
I didn't understand eval, but that was this afternoon and I 
know all about it now :-)

> This avoids starting up a whole new bash process (though I 
> think the evaluated command is still considered a 
> "subshell" - but at least not a separate process.)

was wondering about starting up a new bash process in the 
middle of the script. This will save me from starting a new 
shell.

Thanks
Joe
-- 
Joseph Mack NA3T EME(B,D), FM05lw North Carolina
jmack (at) wm7d (dot) net - azimuthal equidistant map
generator at http://www.wm7d.net/azproj.shtml
Homepage http://www.austintek.com/ It's GNU/Linux!



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