BASH printf array with field separator and newline on last entry

Question

How can I print out an array in BASH with a field separator between each value and a newline at the end.

The closest I can get with a single printf is printf '%s|' "${arr1[@]}" where | is the field separator. The problem with this is there is no line break at the end. Any combination of \n I try to put in there either puts in a line break on every entry or none at all!

Is there a way of doing it on one line or do I need to use printf '%s|' "${arr1[@]}";printf "\n"

Thanks,

Geraint

Answer 1

If you don't want to have the | be printed, you could also remove it and just put in a space or whatever seperator you want to use (e.g. , or -):

printf '%s ' "${arr1[@]}" ; printf '\n'

If you need this more often you should use a function, due to writing the same code over and over is not the best way:

print_array ()
{
  # run through array and print each entry:
  local array
  array=("$@")
  for i in "${array[@]}" ; do
      printf '%s ' "$i"
  done
  # print a new line
  printf '\n'
}

usage:

print_array "${array_name[@]}"

example:

array01=(one two three)
print_array "${array01[@]}"
echo "this should be a new line"

output:

one two three
this should be a new line