RE: [PATCH 3/3] kbuild: rewrite ld-version.sh in shell script

From: David Laight
Date: Sat Dec 12 2020 - 16:49:38 EST


From: Masahiro Yamada
> Sent: 12 December 2020 16:55
>
> This script was written in awk in spite of the file extension '.sh'.
> Rewrite it as a shell script.
...
> +#
> +# Usage: $ ./scripts/ld-version.sh ld
> +#
> +# Print the linker version of `ld' in a 5 or 6-digit form
> +# such as `23501' for GNU ld 2.35.1 etc.
> +
> +first_line="$($* --version | head -n 1)"
> +
> +if ! ( echo $first_line | grep -q "GNU ld"); then
> + echo 0
> + exit 1
> +fi
> +
> +# Distributions may append an extra string like 2.35-15.fc33
> +# Take the part that consists of numbers and dots.
> +VERSION=$(echo $first_line | sed 's/.* \([^ ]*\)$/\1/' | sed 's/^\(^[0-9.]*\).*/\1/')
> +MAJOR=$(echo $VERSION | cut -d . -f 1)
> +MINOR=$(echo $VERSION | cut -d . -f 2)
> +PATCHLEVEL=$(echo $VERSION | cut -d . -f 3)
> +printf "%d%02d%02d\\n" $MAJOR $MINOR $PATCHLEVEL


Hmmmm.....
You've managed to convert an awk script into something that requires
sh, head, grep, sed (twice), and cut (thrice).
Plus (probably) a few sub-shells.

It is quite ease to do it all in all in the shell.

David

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