[Bioperl-l] standardize shebang line in bioperl scripts

[Steven Lembark]

On Wed, 29 Aug 2018 12:19:54 +0100
Carnë Draug <carandraug+dev at gmail.com> wrote:

> Hi
> 
> I was wondering if there's any consensus about what should be used in
> the shebang line.  Looking at the existing scripts, I found:
> 
>     #!perl
>     #!/usr/bin/env perl
>     #!/usr/bin/perl
>     #!/usr/bin/perl -w
> 

POSIX did away with non-absolute path #! lines.

#!/usr/bin/perl is largely unusable as it assumes you are using the
O/S installed versin of perl, which you usually aren't (unless you
want to use 5.8 on Centos or 5.10 on Redhat or 5.16 on Amazon linux).

Net result: "env" is the only sane way to go.

Luvly thing is that env might be installed in /bin/env or /usr/bin/env
depending on Linux vs. BSD vs. SysV roots of whatever you are running
Perl on (let alone Windows...). 

The one most likely to work is:

    #!/usr/bin/env perl

linux habitually installs env into /bin with a symlink in /usr/bin;
BSD & SysV install it in /usr/bin maybe-without a symlink in /bin.

I any case using "/usr/bin/perl" either ties you to decade(s) out of
date perl with the O/S distro or forces you to update the disro perl,
which may break ancient pieces of the distro itself.


-- 
Steven Lembark                                     3920 10th Ave South
Workhorse Computing                               Birmingham, AL 35222
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