bashpipecurly-braces

How to return variables from a curly brackets scoped code?

How do I return variables from curly braces?

For example, how do I get the return value of the command curl outside the curly brackets in the following snippet?

#!/usr/bin/bash

{ # scope for tee
    curl --max-time 5 "https://google.com"
    rc=$?
} | tee "page.html"

echo "return code: $rc"
Solution

  • The reason $rc is not updated in your example is because bash will create a subshell when using a pipe

    One solution to your problem is to use ${PIPESTATUS[@]}:

    #!/usr/bin/bash

curl --max-time 5 "https://google.com" | tee "page.html"

echo "curl return code: ${PIPESTATUS[0]}"

    Another solution is to not use a pipe at all avoiding the subshell for curl:

    #!/usr/bin/bash

{ # scope for tee
    curl --max-time 5 "https://google.com"
    rc=$?
} > >( tee "page.html" )

echo "return code: $rc"