I am getting error “array.sh: 3: array.sh: Syntax error: ”(“ unexpected”

Question

I have written the following code:

#!/bin/bash
#Simple array
array=(1 2 3 4 5)

echo ${array[*]}

And I am getting error: array.sh: 3: a

Answer 1

Given that script:

#!/bin/bash
#Simple array
array=(1 2 3 4 5)

echo ${array[*]}

and assuming:

• It's in a file in your current directory named array.sh;
• You've done chmod +x array.sh;
• You have a sufficiently new version of bash installed in /bin/bash (you report that you have 4.3.8, which is certainly new enough); and
• You execute it correctly

then that should work without any problem.

If you execute the script by typing

./array.sh

the system will pay attention to the #!/bin/bash line and execute the script using /bin/bash.

If you execute it by typing something like:

sh ./array.sh

then it will execute it using /bin/sh. On Ubuntu, /bin/sh is typically a symbolic link to /bin/dash, a Bourne-like shell that doesn't support arrays. That will give you exactly the error message that you report.

The shell used to execute a script is not affected by which shell you're currently using or by which shell is configured as your login shell in /etc/passwd or equivalent (unless you use the source or . command).

In your own answer, you say you fixed the problem by using chsh to change your default login shell to /bin/bash. That by itself should not have any effect. (And /bin/bash is the default login shell on Ubuntu anyway; had you changed it to something else previously?)

What must have happened is that you changed the command you use from sh ./array.sh to ./array.sh without realizing it.

Try running sh ./array.sh and see if you get the same error.