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How does a pipe works?
The problem pertains to simple shell script. I am unable to analyze the
follwing , can any one on the list explain me :
$echo HELLO | read var_name # here I pipe the o/p of echo command to
$echo $var_name # here I check that "HELLO" is
stored in the user defined variable
The above comand works fine. Now consider this
$ read var_name | echo HELLO
<here some i/p has to be fed by the user>
$echo $var_name # I try to see what the variable has been read into
<blank line displayed>
Though the standard i/p waits for some i/p from user, the variable is
not assigned the value.
Why this is so?