Re: Shebang - why are parameters not splitted on whitespace?

[Geralt <usr.gentoo@googlemail.com>]

On Wed, Dec 3, 2008 at 4:56 PM, Américo Wang <xiyou.wangcong@gmail.com> wrote:
> On Wed, Dec 3, 2008 at 3:14 PM, Geralt <usr.gentoo@googlemail.com> wrote:
>> Hi,
>>
>> I've just noticed, that it's not possible to use more than one
>> parameter in a shebang on linux, because everything following the
>> executable path in the shebang is treated as one parameter, so for
>> example
>> #!/bin/awk --re-interval -f
>> in a script called "test.awk" results in a call likes this:
>> /bin/awk "--re-interval -f" ./test.awk
>> when running it with "./test.awk".
>>
>> Is there any reason why the parameters are not split before passing
>> them on to the program?
>
>
> Hello,
>
> I think this behavior is different on different platforms, you can
> find some clues
> in man page of execve(2):
>
>       The  semantics  of  the  optional-arg argument of an interpreter script
>       vary across implementations.  On Linux, the entire string following the
>       interpreter name is passed as a single argument to the interpreter, and
>       this string can include white space.  However, behavior differs on some
>       other  systems.   Some  systems  use the first white space to terminate
>       optional-arg.  On some systems, an interpreter script can have multiple
>       arguments,  and  white  spaces  in optional-arg are used to delimit the
>       arguments
>
> It seems that POSIX doesn't specify this.
>
> Thanks.
>

Hello,

I should have anticipated this objection :-). I'm aware that this is
not consistent among Unix operating systems (you can find more about
it here [1]), but I was specifically refering to linux in this case
and why it handles the shebang arguments as one big string and not as
single arguments for the application.



Geralt.


[1] http://www.in-ulm.de/~mascheck/various/shebang/