How can I take sort bash arguments alphabetically?
$ ./script.sh bbb aaa ddd ccc
and put it into an array such that I now have an array {aaa, bbb, ccc, ddd}
3 Answers
You can do:
A=( $(sort <(printf "%s\n" "$@")) )
printf "%s\n" "${A[@]}"
aaa
bbb
ccc
ddd
It is using steps:
- sort the
arguments list i.e."$@"` - store output of sort in an array
- Print the sorted array
5 Comments
F. Hauri - Give Up GitHub
I don't understand the goal of 1st step: Why not simply
declare -a A=($(sort <(printf "%s\n" "$@"))) ?
anubhava
Sure that step can be eliminated, that is just for demonstration purpose. May I add that core of the answer is in 2nd step not 1st.
that other guy
Users should be aware that this doesn't work with whitespace or special characters.
that other guy
@rici It splits up the result based on IFS, which includes spaces by default.
rici
@thatotherguy:
sortargs() { mapfile -t $1 < <(printf "%s\n" "${@:2}"|sort); }; sortargs A "foo bar" "*" "" $'baz\tcow'; printf "%s\n" "${A[@]}". Still fails on newlines, of course.I hope following 2 lines will help.
sorted=$(printf '%s\n' "$@"|sort)
echo $sorted
This will give you a sorted cmdline args.I wonder though why its needed :)
But anyway it will sort your cmdlines
Removed whatever was not required.
Comments
Here's an invocation that breaks all the other solutions proposed here:
./script.sh "foo bar" "*" "" $'baz\ncow'
Here's a piece of code that works correctly:
array=()
(( $# )) && while IFS= read -r -d '' var
do
array+=("$var")
done < <(printf "%s\0" "$@" | sort -z)
4 Comments
F. Hauri - Give Up GitHub
I downvoted this because I don't know a lot of case where sorting long field with linebreak are really a need. In the other hand, I know a lot of cases where quick sort on small fields may be usefull.
jaypal singh
@F.Hauri It was a poorly written question with no mention of edge cases. I would have down voted the question.
that other guy
@F.Hauri As long as you're doing it for fair and logical reasons and not petty childishness, I'm fine with that.
F. Hauri - Give Up GitHub
@jaypal I agreee, and I won't downvote this answer at all because there is a real effort to present a reliable way of working with null terminated strings, but SO won't let me correct my vote now...
$@