-s enables rudimentary switch parsing for switches on the command
line after the program name but before any filename arguments (or
before an argument of --). Any switch found there is removed from
@ARGV and sets the corresponding variable in the Perl program.
The following program prints "1" if the program is invoked with a
-xyz switch, and "abc" if it is invoked with -xyz=abc.
#!/usr/bin/perl -s
if ($xyz) { print "$xyz\n" }
Do note that a switch like --help creates the variable ${-help},
which is not compliant with "strict refs". Also, when using this
option on a script with warnings enabled you may get a lot of spuâ
rious "used only once" warnings.