Making an array in Linux, using bash

Question

Assume that the Pid of active processes on my machines are 1000 and 2000. I am trying to make an array in Linux such that

The command echo ${Pid_Current[0]} gives 1000 in output

The command echo ${Pid_Current[1]} gives 2000 in output

Here is my code:

declare -a Pid_Current 

Pid_Current=$(ps -aF | tail -n +2 | awk '{print $2}')

However, instead of the desired output I explained above, I receive the following output:

echo ${Pid_Current[0]} gives 1000 2000 in output

echo ${Pid_Current[1]} gives nothing in output

Would you please advise me what part of my code is incorrect?

mata · Accepted Answer · 2015-11-23 14:07:25Z

1

In bash array assignment is done by enclosing the expression in parenthesis, so to use array assignment you need to write:

Pid_Current=($(ps -aF | tail -n +2 | awk '{print $2}'))

Without parenthesis the result of the expression is assigned to Pid_Current[0]

answered Nov 23, 2015 at 14:07

mata

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