Re: [Qemu-devel] [PATCH 4/4] configure: check for supported Python 2.x versions

[Lluís Vilanova]

Stefan Hajnoczi writes:

> The tracetool code requires Python 2.4, which was released in 2004.
> Check for a supported Python version so we can give a clear error
> message.

> Signed-off-by: Stefan Hajnoczi <address@hidden>
> ---
>  configure |    7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)

> diff --git a/configure b/configure
> index 15bbc73..39c7ac2 100755
> --- a/configure
> +++ b/configure
> @@ -1247,9 +1247,10 @@ fi
 
>  # Note that if the Python conditional here evaluates True we will exit
>  # with status 1 which is a shell 'false' value.
> -if ! "$python" -c 'import sys; sys.exit(sys.version_info[0] >= 3)'; then
> -  echo "Python 2 required but '$python' is version 3 or better."
> -  echo "Use --python=/path/to/python to specify a Python 2."
> +if ! "$python" -c 'import sys; sys.exit(sys.version_info[0] != 2 or 
> sys.version_info[1] < 4)'; then
> +  echo "Cannot use '$python', Python 2.4 or later is required."
> +  echo "Note that Python 3 or later is not yet supported."
> +  echo "Use --python=/path/to/python to specify a supported Python."
>    exit 1
>  fi

This looks more readable to me:

    sys.exit(sys.version_info < (2,4) or sys.version_info >= (3,))


Lluis

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