perform echo and awk inside a string

h0ujun · February 8, 2012, 2:14am

hi,

just wanted to make a shortcut of this one
a="a b c"
b=`echo $a | awk '{print $2}'`
echo "the middle is $b"

why can't i do this:
a="a b c"
echo "the middle is ${`echo $a | awk '{print $2}'`}" <- bad substitution :wall:

thanks

balajesuri · February 8, 2012, 2:15am

echo "the middle is `echo $a | awk '{print $2}'`"

knight_eon · February 8, 2012, 2:17am

It should be:

 
a="a b c"
echo "the middle is $(echo $a | awk '{print $2}')"

[PS: U should keep your Codes/Output in CODE Tag. Mods don't like unformatted codes and output. SO next time please use Code Tags]

balajesuri · February 8, 2012, 2:23am

Either way is fine. Backticks are used in post #2.. $() will work equally well.

knight_eon · February 8, 2012, 2:36am

Oopps... We both posted nearly at the same time so did not see ur reply
I like $() more then `` because of aeshetic value and less confusion over `` and ''

Scrutinizer · February 8, 2012, 2:59am

Plus in the backquote style command substitution you sometimes need to escape certain things (for example when nesting) whereas in $() this is much more straightforward..

ahamed101 · February 8, 2012, 3:18am

Plus, backticks is obsolete, $( ) is recommended.

--ahamed