Cygwin bash syntax error - but script run perfectly well in Ubuntu

Question

#!/bin/bash
if test "$#" == "4"; then echo "$*"; else echo "args-error" >&2; fi;

This little code snippet troubles me a lot when I tried to run it on both Ubuntu and Cygwin.

Ubuntu runs bash version 4.0+ whereas Cygwin runs 3.2.49; But I reckon version collision shall not be the cause of this, this code runs well under fedora 10 which is also using bash version 3.+

So basically I am wondering if there is a way to code my script once and for all so there are not to have this awful issue later on.

Many thanks in advance.

Edited : I don't have Cygwin by hand at the moment but from my memory, it keeps saying something like couldn't resolve undefined token "fi" something like that.

Edited : well,the original form is like this, just found from server :

#!/bin/bash
if ["$#" == "4"];
    then echo "$*";
    else echo "args-error" >&2;
fi;

Console complains :

$ ./test.sh 1 2 3
./test.sh: line 2: [3: command not found
args-error

I am also wondering how come that stderr says something goes wrong - command not found - but can still print out the answer?

Answer 1

You need whitespace around the [ and ].

#!/bin/bash
if [ "$#" == "4" ];
    then echo "$*";
    else echo "args-error" >&2;
fi;