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NAME

FFI::C::StructDef - Structured data definition for FFI

VERSION

version 0.15

SYNOPSIS

In your C code:

#include <stdint.h>
#include <stdio.h>
typedef struct {
uint8_t red;
uint8_t green;
uint8_t blue;
} color_t;
void
print_color(color_t *c)
{
printf("[%02x %02x %02x]\n",
c->red,
c->green,
c->blue
);
}

In your Perl code:

use FFI::Platypus 1.00;
my $ffi = FFI::Platypus->new( api => 1 );
# See FFI::Platypus::Bundle for how bundle works.
$ffi->bundle;
my $def = FFI::C::StructDef->new(
$ffi,
name => 'color_t',
class => 'Color',
members => [
red => 'uint8',
green => 'uint8',
blue => 'uint8',
],
);
my $red = Color->new({ red => 255 });
my $green = Color->new({ green => 255 });
$ffi->attach( print_color => ['color_t'] );
print_color($red); # [ff 00 00]
print_color($green); # [00 ff 00]
# that red is a tad bright!
$red->red( 200 );
print_color($red); # [c8 00 00]

DESCRIPTION

This class creates a def for a C struct.

CONSTRUCTOR

new

my $def = FFI::C::StructDef->new(%opts);
my $def = FFI::C::StructDef->new($ffi, %opts);

For standard def options, see FFI::C::Def.

members

This should be an array reference containing name, type pairs, in the order that they will be stored in the struct.

trim_string

If true, fixed-length strings should be treated as null terminated strings and be trimmed.

METHODS

create

my $instance = $def->create;
my $instance = $def->class->new; # if class was specified
my $instance = $def->create(\%init);
my $instance = $def->class->new(\%init); # if class was specified

This creates an instance of the struct, returns a FFI::C::Struct.

You can optionally initialize member values using %init.

trim_string

my $bool = $def->trim_string;

Returns true if fixed-length strings should be treated as null terminated strings and be trimmed.

SEE ALSO

FFI::C
FFI::C::Array
FFI::C::ArrayDef
FFI::C::Def
FFI::C::File
FFI::C::PosixFile
FFI::C::Struct
FFI::C::StructDef
FFI::C::Union
FFI::C::UnionDef
FFI::C::Util
FFI::Platypus::Record

AUTHOR

Graham Ollis <plicease@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2020-2022 by Graham Ollis.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.