Bash: echo from command while it's executing

Question

I want to see the entire output (not just the return value) of a script while it's executing via bash, like this:

#!/bin/sh    
cmd="$(script.py $arg)"

script.py prints multiple lines while executing, but I'm unable to see them in bash. Is there a way to maybe pipe the output to stdout?

score 1 · Accepted Answer · 2012-10-05 05:22:21Z

1

this will display each line "produced" by your script while it is running:

while read line; do echo $line; done < <(script.py $arg 2>&1)

it will also, as suggested in the post above, redirect stderr to stdout

answered Oct 5, 2012 at 5:16

user904990

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Comments

Vaughn Cato · Accepted Answer · 2012-10-05 05:10:54Z

1

Perhaps it is being output to stderr. Try this:

#!/bin/sh    
cmd="$(script.py $arg 2>&1)"

answered Oct 5, 2012 at 5:10

Vaughn Cato

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