$ od -c -N2 hello.pl
    0000000   #   !
[download]

Interesting, TimToady, I didn't know the od command:

$ od -c -N2 1.hello.pl
0000000   #   !
0000002
$ man od
$ od -c -N8 1.hello.pl
0000000   #   !   /   u   s   r   /   b
0000010
$
[download]

I bet perl isn't /usr/bin/perl and which perl will reveal more information.

Re-parented to non-reaped dupe by planetscape

1) You can edit errors such as you made here (by failing to include code tags) by updating (adding code tags) rather than by duping the question, as you did in id:/543444. Please update, rather than creating a new question, in the future. On the other hand, until we fix the the dupe situationdone please see chromatic's response to your other post, in case you're showing us historical output: did you reinstall or update perl recently?

2) If the your illustration is not suffering from fatfingers or editing, what is not working? I see cat spitting out plausible code with a perfectly fine shebang --
#!/usr/bin/perl -W
... and execution of hello.pl emitting what I would expect from your code.

thanks for editting my post.
it works when i use 'perl' explicitly in front of script name,
but it doesn't work when i just type './hello.pl'.

'./hello.pl' spits out nothing.
'perl hello.pl' works.

i have upgraded the kernel recently.
but not the perl.

OTOH, I see you also posted the exact same question to clpmisc. If anything relevant and different from what comes out here pops up there, then be sure to report for the benefit of others, and vice-versa.

1. will not run from shebang
2. will run with "perl myscript"
3. will look fine with "cat myscript".
[download]

Actually, because of the -W, it would work with CRs:

$ od -c 543561.pl
0000000  #   !   /   u   s   r   /   b   i   n   /   p   e   r   l
0000020  -   W  \r  \n  \r  \n   p   r   i   n   t       "   H   e   l
0000040  l   o   ,       W   o   r   l   d   !   \   n   "   ;  \r  \n
0000060
$ 543561.pl
Hello, World!
[download]

I've had problems when I copied a shebang over from another file and that contained gremlins (entities not supported by Perl). For what it's worth.

if this is a unix platform type

whereis perl
[download]

into the prompt. it'll tell you all your perl locations located in your $PATH

Did you make the file executable?

I would expect an error message if not, but it's worth checking anyway.

There's also the possibility that your perl executable might have been corrupted somehow. Try replacing the perl executable somehow — perhaps by "updating" the software using whatever software management system is standard for your OS.

I don't know if that's problem, but shouldn't that be -w instead of -W?

Also, what OS are you using? Windows has issues running .pl's directly, although I think the problems might be limited to in/out redirection. (See pl2bat.)

Update: Apparently, -W is a valid option. I should have checked first.

I'm reaching here, but another possibility is to type type perl at the command line, which will give you a bit more information than which perl. In particular, it will let you know if your perl is a link to another location (it may say something like, 'perl is hashed').

You may want to check your $PATH, which might give you a hint about what's going on, or where things are being looked for. You might also check your .profile and .bashrc (or whatever the corresponding files would be for your setup), to see whether something in them has been changed.

chmod +x hello.pl
[download]

Jack

Note that Kate has a BOM option that, if checked, adds a BOM mark as the first three characters in the file. They doesn't show in Kate or Vim. You can see them with a hex editor (like Bless) as "EF BB BF" ("..." in the character section). I was stumped before I found this out and I've no idea how this option came to be checked in my case. On top of that Bless couldn't save a changed file due to "Not enough space on device bla bla..." which in it's turn was fixed by entering "/tmp" under "Edit","Preferences". A problem never comes alone.