I prefer 

{
   open local *STDOUT, '>', \$buf;
   ...
}

[download]
over 
open TEMP, '>', \$buf;
my $old_select = select(TEMP);
...
select($old_select);

[download]

since the former restores STDOUT even in the case of exceptions. The former, however, doesn't work if someone has previously called select. I guess the comprehensive solution would be: 

{
   my $old_select = select();
   my $handle = on_release { select($old_select); };
   open local *STDOUT, '>', \$buf;
   select(STDOUT);
   ...
}

[download]

It even handles exceptions thrown by signal handlers.

Updated.

In reply to Re^3: Need Help: Capture Print Outputs from a Function by ikegami
in thread Need Help: Capture Print Outputs from a Function by mnj200g

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