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

Updated answer:

You need a space after [ otherwise ["$#" is evaluated to for example [3 which doesn't exist. Try this:

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

---

It works for me. I would guess that you are getting an error like this:

test.sh: line 2: $'\r': command not found
test.sh: line 3: $'\r': command not found

This can happen because you have edited the file using Windows-style line endings but Bash expects Unix-style line endings. To fix the file, try running this command:

dos2unix test.sh

You of course need to change the filename to the actual filename of your script.

Answer 2

You need whitespace around the [ and ].

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

Answer 3

In your edit to show the 'original form' the problem would seem to be that you're missing a space between the [ and the "

Answer 4

try to use operator '=' instead of '==' . And also add one space after [ and another before ] as folowing

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

Or even try '-eq' instead of '=='

if [ "$#" -eq "4" ];

Because in some systems, it does not accept the operator '=='