Re^2: Issue with #!usr/bin/perl

Actually on Windows, the shebang line is not ignored. The Operating System ignores it, but Perl pays attention. Compare:

#!/usr/bin/perl
print undef;
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with:

#!/usr/bin/perl -w
print undef;
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The former issues no warning; the latter warns about using an uninitialized value.

This is because in Perl, the shebang line performs two roles. It's used by Unix-like operating systems as a "dispatch mechanism" - to decide which program should interpret the script. And on all operating systems Perl parses it looking for command-line options. It doesn't honour all command line options found there (e.g. -M) but does some (like -w and -t).

package Cow { use Moo; has name => (is => 'lazy', default => sub { 'Mooington' }) } say Cow->new->name

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Re^3: Issue with #!usr/bin/perl by DrHyde (Prior) on Mar 14, 2013 at 11:25 UTC
There's also this useful trick for writing perl scripts that will run using whatever is the first perl in the $PATH: `#!/bin/sh exec perl -x $0 #!perl # your perl code goes here` [download] "But why not use `#!/usr/bin/env perl`?", I hear you cry. Because `env` isn't always in /usr/bin - it's in /bin on some obscure platforms - and there can be "issues" with passing arguments to the executable via `env`.	[reply] [d/l] [select]
Re^3: Issue with #!usr/bin/perl by nagalenoj (Friar) on Mar 13, 2013 at 09:49 UTC
Thanks for the clarification. As I haven't used windows machine for perl scripting, never encounter such and I didn't know this before. Thanks.	[reply]
Re^3: Issue with #!usr/bin/perl by Anonymous Monk on Feb 02, 2018 at 14:54 UTC
what's the difference between shebang -w vs. use strict; use warnings; ? Thinking of putting a shebang at the top of all my scripts that say #!/perl/shebang - be a win32 japh you know this is pointless, even with the -w.	[reply]
Re^4: Issue with #!usr/bin/perl by Anonymous Monk on Feb 02, 2018 at 14:57 UTC
what's the difference between shebang -w vs. use strict; use warnings; ? "use warnings" is lexical and -w is global. What's wrong with * w* and $^W	[reply]