Here is an example way to do what you want for educational purposes (Parallel::ForkManager is really the way to go in production code).

It is possible to loop through functions by taking references with the \& syntax: 
sub sub1 { print 'sub1 ran' }
sub sub2 { print 'sub2 ran' }

my @refs = (\&sub1, \&sub2);
$_->() foreach @refs;

[download]
Fork failure is indicated by an undef return value by the fork function. If you want to go on with processing in a non-parallel manner when fork fails, you can just check if it's defined. Full example: 
use strict;
use warnings;
use POSIX ':sys_wait_h';

my @subs_to_run = (
    \&sub1,
    \&sub2,
    \&sub3,
    \&sub4,
    \&sub5,
);
foreach my $sub (@subs_to_run) {
    my $is_parent = fork;  # try to fork
    next if $is_parent;    # both child and fork failure will be false

    $sub->();  # we're in the child or fork failed, run the sub

    exit if defined $is_parent;  # exit only if actually forked
}

1 while waitpid(-1, WNOHANG) > 0;  # wait for all children

[download]

In reply to Re^3: Learning to use fork() by kroach
in thread Learning to use fork() by ovedpo15

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