Array diclaration shell script

sureshkumar.challa · 04-17-2013, 06:09 AM

Hi Sir,

Please help me.

How to declare array in shell script?

i am using bash shell.

when i declared like this, It was showing error ---> "(" unexpected

Ex:-
#!/bin/bash
array_name=(value1 value2 value3)
echo {array_name[1]}

output:-
showiing error like ( Syntax error: "(" unexpected )

druuna · 04-17-2013, 06:15 AM

Although I do see a syntax error (missing $ sign), I'm not sure why you get this specific error.

It does seem to work on my side:

Code:

$ cat foo.sh
#!/bin/bash

array_name=(value1 value2 value3)
echo ${array_name[1]}

$ ./foo.sh
value2

$ bash --version
GNU bash, version 4.1.5(1)-release (x86_64-pc-linux-gnu)

EDIT: Also works with bash version 3.1.17(1)

Snark1994 · 04-17-2013, 06:19 AM

Code:

#!/bin/bash
array_name=(value1 value2 value3)
echo ${array_name[1]}

works fine for me, and your original code doesn't give me an error either (both with bash 4.2.45). Have you copied and pasted your code into your post?

nkiran · 04-17-2013, 06:34 AM

Quote:

Originally Posted by sureshkumar.challa

Hi Sir,

Please help me.

How to declare array in shell script?

i am using bash shell.

when i declared like this, It was showing error ---> "(" unexpected

Ex:-
#!/bin/bash
array_name=(value1 value2 value3)
echo {array_name[1]}

output:-
showiing error like ( Syntax error: "(" unexpected )

Your script works fine on my machine after a small correction. You have missed the $ before {array_name[1]}
#!/bin/bash
array_name=(value1 value2 value3)
echo ${array_name[1]}

Done!
I can't understand the relation between the error message and this correction. Can you copy paste your script here?

konsolebox · 04-17-2013, 07:56 AM

You're probably not calling the script with a real bash. And I hope you're not actually trolling.

shivaa · 04-17-2013, 08:27 AM

Once go through this article here.

You can declare arrary as:

Code:

arrary_name=(val1 val2 val3...)

Then use arrary as:

Code:

#!/bin/bash 
arrary_name=(val1 val2 val3...)
for val in "${arrary_name[@]}"
do
command1
command2
done

David the H. · 04-18-2013, 02:59 PM

My suspicion is that the OP is attempting to execute the script with sh directly, like this:

Code:

sh scriptname.sh

If so, then the #!/bin/bash shebang at the top of the script is being ignored and it's being parsed by /bin/sh instead. And if /bin/sh is symlinked to dash or a similar strictly posix shell, then arrays aren't supported.

If a script has the proper shebang, then just chmod it to be executable and launch it directly:

Code:

./scriptname.sh    #assuming pwd contains the script.

This way it will be interpreted by the shell specified in the shebang.

And please use ***[code][/code]*** tags around your code and data, to preserve the original formatting and to improve readability. Do not use quote tags, bolding, colors, "start/end" lines, or other creative techniques.