Set +A usage

Shell Programming and Scripting
1

Hi Team,

Could you please explain me the usage of set +A command in setting values to an array ?

Also, what does the below command do ?

set +A filesSent ${filesSent[*]},${file}${FLAGEXT}

Thanks in advance.

Regards,
Mohan

2

set -A or set +A works only in ksh, not in bash.

set -A arrayname list of values

Add echo before cmdline = see the result = howto shell expand commandline = after
that has done command.

You can make the list so many ways

  • using some variable like $*
  • cmd like $(who)
  • give valuelist val1 val2 val3 "val4 is longer" val5
# number of elements in array
${#array[*]}

# all elements
${array[*]}

1st element index is 0

echo "1st:${array[0]}"
#
last=${#array[*]}
((last -= 1 ))
echo "last:${array[$last]}"

And last, shift array - remove 1st element

set -A array "${array[@]:1}"
3

KshJi, I just need only clarification.. What is the differeence between +A and -A ?

4

Man says something but I have seen any differences. If arg list is empty, in both case array include still values. Maybe the reason is +/- which is normal for set options. Added only support for both, even result is same.

---------- Post updated at 11:09 AM ---------- Previous update was at 11:06 AM ----------

It is easy to hope:
set -A remove from the array
set +A add to the array
but no.