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RE: read command available?


"neal somos" wrote:
> The read command is supposedly a shell builtin.
>
> Strangely enough, the first time I tried the
> example given with ksh, I got the exact same response.
>
> However on later attempts, I got what was expected.
> I find this odd.
>
> /bin/sh and bash both handle this just fine.
> I can't speak for ksh, but maybe its time to
> switch to a different shell?
>
> neal

This really is OT on this list, but as we've started...

 You have to be aware of some automatic optimizations, I'm not sure about
ksh - but bash does some subshell'ing in this situation. The following DOES
indicate that ksh shouldn't, but then you never know how up to date the man
page is.

-- man ksh excerpt --
Note: Some shells (but not this one) execute control structure commands
in a subshell when one or more of  their  file  descriptors  are  redi-
rected,  so  any  environment  changes  inside  them  may  fail.  To be
portable, the exec statement should be used instead  to  redirect  file
descriptors before the control structure.

-- and right after it --
( list )
       Execute list in a subshell.  There is no implicit  way  to  pass
       environment changes from a subshell back to its parent.


/Hannu E K Nevalainen, B.Sc. EE - 59+16.37'N, 17+12.60'E         --72-->

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