CODEWITHSUNDEEP
shell
user3165241
user3165241

Reputation: 23

How to use the single dimensional array in shell script and display the array?

results=
results['startlogdate']="Start time"
results['endlogdate']="$finish_time"
echo "${results[*]}"

I am trying to initialise the array and adding the value to array and echo the array. The code above is my attempt.

Upvotes: 0

Views: 1170

Answers (3)

aks
aks

Reputation: 2346

In bash scripts, there are two kinds of arrays: numerically indexed and associatively indexed.

Depending on the version of your shell, associatively indexed arrays might not be supported.

Related to the example in your question, the correct syntax to obtain the values of the array, each as a separate word, is:

"${results[@]}"

To get the keys of the associative array, do:

"${!results[@]"

The script below demonstrates the use of an associative array. For more details, see the Arrays section in the bash manpage.

#!/bin/bash
# tst.sh
declare -A aa
aa[foo]=bar
aa[fee]=baz
aa[fie]=tar
for key in "${!aa[@]}" ; do
  printf "key: '%s'    val: '%s'\n" $key "${aa[$key]}"
done
echo "${aa[@]}"
exit

Here is the output:

$ bash tst.sh
key: 'foo'    val: 'bar'
key: 'fee'    val: 'baz'
key: 'fie'    val: 'tar'
tar bar baz

Finally, I've made available my library of array functions (aka "lists"), which I've been using for many years to make managing data in arrays easy.

Check out https://github.com/aks/bash-lib/blob/master/list-utils.sh

Even if you choose not to make use of the library, you can learn a lot about arrays by reading the code there.

Good luck.

Upvotes: 1

user3171841
user3171841

Reputation: 44

finish_time=`date`

results[0]="Start time"

results[1]="$finish_time"

echo ${results[@]}

Output: Start time Wed Jan 8 12:25:14 IST 2014

Number of elements: echo ${#results[@]}

Arrays in bash are zero indexed, so ${results[0]} will be "Start time" and ${results[1]} will be "Wed Jan 8 12:25:14 IST 2014"

Upvotes: 0

Fidel
Fidel

Reputation: 1037

If want to use array in bash. you will be able to do in two ways.

  1. Declare an array in bash.
    declare -a Unix=('Debian' 'Red hat' 'Red hat' 'Suse' 'Fedora');
    echo ${Unix[0]} # Prints the first element
    echo ${Unix[*]} # prints all the elements of an array

  2. Use directly (i.e) without declare. Unix[0]='Debian';Unix[1]='Red hat'

Upvotes: 0

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