The issue is that you don't want to forget to free the buffer.

Another approach is to not use FFI directly, but hide the glue in a module, where you could use an END block to ensure it's freed on exit. 

package My::StringUtils;

use strict;
use warnings;

use Export qw( import );
use FFI::Platypus 2.00;

our @EXPORT_OK = qw( string_reverse );
 
my $ffi = FFI::Platypus->new(
   api => 2,
   lib => './string_reverse.so',
);
 
$ffi->attach( string_reverse => [ 'string' ] => 'string' );
 
END { string_reverse( undef ); }

1

[download]
use strict;
use warnings;
use feature qw( say );

use My::StringUtils qw( string_reverse );

say string_reverse( "Hello world" );

[download]

(Fine, you don't need a module to use END, but using a module means you don't forget to use END.)

In reply to Re: FFI::Platypus: Replace malloc with GC_MALLOC? by ikegami
in thread FFI::Platypus: Replace malloc with GC_MALLOC? by karlgoethebier

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