hi, all monks:

I notice that, $clientSocket->recv( $buffer, $length) can pass the data back to $buffer, even though the $buffer is value-passed, rather than ref-passed.

I write a test subroutine, if I want to pass the data back from a subroutine, I need to pass the variable by ref. like this: 

my $buffer;
foosub( \$bufffer );
print $buffer, "\n";

sub foosub
{
    my $rs_buffer = shift;
    $$rs_buffer = "Hello, world";
}

[download]
if I pass it by value, it gets nothing back: 
my $buffer;
foosub( $buffer);
print $buffer, "\n";

sub foosub
{
    my $buffer = shift;
    $buffer = "Hello, world";
}

[download]

so, why the recv() can pass the data back by a value-passed?

In reply to How $clientSocket->recv( $buffer, $length) pass the data back by a value-passed? by sunshine_august

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