use v5.030; use PDL; use MCE; srand(3); MCE->new( max_workers => 4, user_func => sub { MCE->say(MCE->wid, " ", rand()); } )->run; #### $ perl ex.pl | sort 1 0.455586975281225 2 0.224720416431413 3 0.993853857581602 4 0.76298729873179 $ perl ex.pl | sort 1 0.778804464106546 2 0.547937905256735 3 0.317071346406923 4 0.0862047875571115 $ perl ex.pl | sort 1 0.49638699840671 2 0.265520439556898 3 0.0346538807070864 4 0.803787321857275 #### # The PDL module 2.062 ~ 2.089 exports its own srand() function, that # silently clobbers Perl's srand function, and does not seed Perl's # pseudo-random generator. https://perlmonks.org/?node_id=11159773 if ( $INC{'PDL/Primitive.pm'} && PDL::Primitive->can('srand') ) { # Call PDL's random() function if exported i.e. use PDL. my $caller = caller(); local $@; $caller = caller(1) if ( $caller =~ /^MCE/ ); $caller = caller(2) if ( $caller =~ /^MCE/ ); $caller = caller(3) if ( $caller =~ /^MCE/ ); $self->{_seed} = eval "$caller->can('random')" ? int(PDL::Primitive::random() * 1e9) : int(CORE::rand() * 1e9); } else { $self->{_seed} = int(CORE::rand() * 1e9); } #### if ( $INC{'PDL/Primitive.pm'} ) { ... } #### $self->{_seed} = int(CORE::rand() * 1e9);