Re: Syntax Question...

[Chet Ramey]

On 8/18/11 9:37 AM, Greg Wooledge wrote:

>>    The  word  following the redirection operator in the following descrip-
>>    tions, unless otherwise noted, is subjected to brace  expansion,  tilde
>>    expansion, parameter expansion, command substitution, arithmetic expan???
>>    sion, quote removal, pathname expansion, and  word  splitting.   If  it
>>    expands to more than one word, bash reports an error.
>>
>> It seems to leave off variable expansion.
> 
> I don't understand this... either it should be reporting an error, or
> it should *not* be expanding the variable.  It doesn't seem to report
> an error on multiple-file pathname expansions either:
> 
> imadev:~$ read a <<< *.pdf
> imadev:~$ echo "$a"
> *.pdf
> 
> In fact, it's not even performing the expansion, as far as I can tell.

The quoted paragraph applies to all redirection operators (and parameter
and variable expansion are still identical).  The description of <<<
notes that it does not perform pathname expansion at all.

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/