Reading command line switches

Just in has asked for the wisdom of the Perl Monks concerning the following question:

Good morrow all.

I'd like to be able to determine what command line switches perl was run with. In the following, how could I print out -w and -MMath::Trig?

C:/>perl -w -MMath::Trig try.pl
Name "main::old" used only once: possible typo at try.pl line 6.
try.pl = []
Use of uninitialized value in print at try.pl line 6.
C:/>cat try.pl
local $" = q{], [};
local $| = 1;

print "$0 = [@ARGV]\n";

print $old[1];
C:/>
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Re: Reading command line switches by BrowserUk (Patriarch) on Mar 16, 2011 at 02:21 UTC
On windows, you can use an API to retrieve the command line used to start the current process. You can get at this API through either Inline::C or Win32::API: `use Inline C => Config => BUILD_NOISY => 1; use Inline C => <<'END_C', NAME => 'junk', CLEAN_AFTER_BUILD => 0; SV *getCommandLine( ) { return newSVpv( GetCommandLine(), 0 ); } END_C print getCommandLine(); __END__ C:\test>getCmdLine.pl -x -P -Mfred /some=other "C:\Perl64\bin\perl.exe" "C:\test\getCmdLine.pl" -x -P -Mfred /some=o +ther` [download] Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l]
Re^2: Reading command line switches by Just in (Sexton) on Mar 16, 2011 at 02:53 UTC
Nice one! This works for me. Thank you very much.	[reply]
Re: Reading command line switches by ww (Archbishop) on Mar 16, 2011 at 01:58 UTC
Please clarify: Do you mean print to <STDOUT>, a log, or dead trees? Is there some reason use of the mark-one eyeball (and perhaps, Win's command line editing capabilities) is inadequate? And what is the point of `cat`ing the pointless code in `try.pl`?	[reply]
Re^2: Reading command line switches by Just in (Sexton) on Mar 16, 2011 at 02:42 UTC
I would like access to the switches, printing is irrespective. However, if it is of importance then STDOUT is a good place for it. `cat` was purely meant as an FYI to suggest that I did look in @ARGV before posting. In fact dare I say, it also suggests STDOUT, (negat\|answer)ing your first question. The code will be executed by other people, and they might put any number of perl switches in on the command line which I would like to be able to determine.	[reply] [d/l]