I would like the shell print every new line with no space and remove the empty line space as well

Question

My shell is printing the output as shown below.

$ echo ${mount_check[*]} |tr "." "\n"
File system /abc is NOT mounted
 File system /xyz is NOT mounted

$

I had tried using echo "${mount_check[*]}" however that didn't print the output the way I wanted.

I would like the shell print every new line with no space and remove the empty line space as well as shown below.

File system /abc is NOT mounted
File system /xyz is NOT mounted

As requested by David and tripleee adding the full code.

fstable=( $(awk '!/bind|swap|shm/ && $1 !~/#|^$/ && !/^ +$/ { print $2 }' /etc/fstab))
mount_check=($(for mount in "${fstable[@]}"; do
if [[ -z $(findmnt -m "$mount") ]]
then
echo "File system $mount is NOT mounted."
fi
done))

What is in `mount_check` and how are you populating the array? Show us `declare -p mount_check` — David C. Rankin, Jan 19 '20 at 08:17
How did you populate `mount_check` in the first place? What does it contain, exactly? You have multiple quirks in your `echo` statement and we can't tell if those are beginner errors or something you do on purpose. `echo "${mount_check[@]}"` might do exactly what you want, or at least provide some insights. See also [When to wrap quotes around a shell variable?](https://stackoverflow.com/questions/10067266/when-to-wrap-quotes-around-a-shell-variable) — tripleee, Jan 19 '20 at 08:19
I had in fact tried echo "${mount_check[@]}" .This is how the array is made. ......mount_check=($(for mount in "${fstable[@]}"; do if [[ -z $(findmnt -m "$mount") ]] then echo "File system $mount is NOT mounted." fi done)) — rony thomas, Jan 19 '20 at 08:20
Not to be too dense, but where does `fstable` come from? `lsblk`? Your `/etc/fstab`? — David C. Rankin, Jan 19 '20 at 08:23

score 1 · Answer 1 · answered Jan 19 '20 at 15:43

Assuming your goal is to create an array mount_check[] with the status of all mounts, this loop:

mount_check=($(for mount in "${fstable[@]}"; do
if [[ -z $(findmnt -m "$mount") ]]
then
echo "File system $mount is NOT mounted."
fi
done))

should be this instead:

mount_check=()
for mount in "${fstable[@]}"; do
    mount_status=$(findmnt -m "$mount")
    if [[ -z "$mount_status" ]]
    then
        mount_status="File system $mount is NOT mounted."
    fi
    mount_check+=( "$mount_status" )
done

RavinderSingh13 · Answer 2 · 2020-01-19T15:33:19.813

I am not sure about your complete requirement, so going by your question specific to fix your problem.

awk solution:

echo "${mount_check[*]}" | awk -F'mounted.' '{gsub(/ File/,"File");print $1 FS ORS $2 FS}'

OR non-one liner for of above solution:

echo "${mount_check[*]}" |\ 
awk -F'mounted.' '
{
  gsub(/ File/,"File")
  print $1 FS ORS $2 FS
}'

I am considering that your output will always going to have File string in output.

What this solution will take care of is:

This will NOT print space which is coming in your 2nd line when you used tr command.
2nd thing it will take care of is, the empty line, which will NOT be printed.

If you want to stick with your code tr one then try following.

echo "${mount_check[*]}" |tr '.' '\n' | sed -E 's/^ +//g;/^$/d'

score 0 · Answer 3 · answered Jan 19 '20 at 08:54

0

Assuming you never used those variables for anything else, you can simply add those tweaks to the Awk script itself.

awk '!/bind|swap|shm/ && $1 !~/#|^$/ && !/^ +$/ {
    p = $2 ; sub(/[.]/, "", p); print p}' /etc/fstab

answered Jan 19 '20 at 08:54

tripleee

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I would like the shell print every new line with no space and remove the empty line space as well

3 Answers3