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# 1  
Old 10-12-2009
read and IFS


This is out of curiosity:
I wanted to extract year, month and date from a variable, and thought that combining read and IFS would help, but this doesn't work:

echo "2010 10 12" | read y m d

I could extract the parts of the date when separated by a -, and setting IFS in a subshell:
r=$(echo '2010-10-12' |(IFS='-'; read y m d; echo $y $m $d))

Any explanation why the first doesn't work?


# 2  
Old 10-12-2009
In ksh:
echo "2010 10 12" | read y m d

In Bash (and newer ksh's):
read y m d <<< "2010 10 12"

Using IFS:
echo '2010-10-12'  | IFS='-' read y m d
echo $y $m $d
2010 10 12

IFS='-' read y m d <<<  "2010-10-12"
echo $y $m $d
2010 10 12

# 3  
Old 10-12-2009
Thanks scottn for the clarifications.
Any idea why read <<< behaves differently from echo "" | read

# 4  
Old 10-12-2009

The bash manpage describes <<< as a "here string", a variant of a here document.

echo ... | read ... is just a plain old pipe.

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