How to correctrly create and read the pointer to array of structures in node-ffi












0















Node-ffi has lack of documentation



I am trying to use this function https://docs.microsoft.com/en-us/windows/desktop/api/ras/nf-ras-rasenumconnectionsw



const ffi = require( 'ffi-napi' );
const ref = require( 'ref' );

var myobj = ref.types.void;
var myobjPtr = ref.refType( myobj );
var myobjPtrPtr = ref.refType( myobjPtr );
var long1 = ref.refType( 'long' );
var long2 = ref.refType( 'long' );

var firstVar = ref.alloc( myobjPtrPtr );
var longVar1 = ref.alloc( 'long' );
var longVar2 = ref.alloc( 'long' );

let ras = new ffi.Library( 'Rasapi32.dll', {
'RasEnumConnectionsW': [
'long', // Return value - DWORD
[ // Arguments
// Pointer to a buffer that receives, on output, an array of RASCONN structures,
// one for each RAS connection.
myobjPtrPtr, // LPRASCONNW

// Pointer to a variable that, on input, contains the size, in bytes, of the buffer
// specified by lprasconn.
long1, // LPDWORD

// Pointer to a variable that receives the number of RASCONN structures written to
// the buffer specified by lprasconn.
long2 // LPDWORD
]
]
});

ras.RasEnumConnectionsW( firstVar, longVar1, longVar2 );

console.log( ref.deref( firstVar ) );


Right now node-ffi gives be UintArray8. Not array of strings, not array of objects










share|improve this question




















  • 1





    You're meant to provide a buffer (of a size that you choose and specify) for the information to be returned in. It looks like you're just passing an uninitialised pointer.

    – Jonathan Potter
    Nov 21 '18 at 11:28
















0















Node-ffi has lack of documentation



I am trying to use this function https://docs.microsoft.com/en-us/windows/desktop/api/ras/nf-ras-rasenumconnectionsw



const ffi = require( 'ffi-napi' );
const ref = require( 'ref' );

var myobj = ref.types.void;
var myobjPtr = ref.refType( myobj );
var myobjPtrPtr = ref.refType( myobjPtr );
var long1 = ref.refType( 'long' );
var long2 = ref.refType( 'long' );

var firstVar = ref.alloc( myobjPtrPtr );
var longVar1 = ref.alloc( 'long' );
var longVar2 = ref.alloc( 'long' );

let ras = new ffi.Library( 'Rasapi32.dll', {
'RasEnumConnectionsW': [
'long', // Return value - DWORD
[ // Arguments
// Pointer to a buffer that receives, on output, an array of RASCONN structures,
// one for each RAS connection.
myobjPtrPtr, // LPRASCONNW

// Pointer to a variable that, on input, contains the size, in bytes, of the buffer
// specified by lprasconn.
long1, // LPDWORD

// Pointer to a variable that receives the number of RASCONN structures written to
// the buffer specified by lprasconn.
long2 // LPDWORD
]
]
});

ras.RasEnumConnectionsW( firstVar, longVar1, longVar2 );

console.log( ref.deref( firstVar ) );


Right now node-ffi gives be UintArray8. Not array of strings, not array of objects










share|improve this question




















  • 1





    You're meant to provide a buffer (of a size that you choose and specify) for the information to be returned in. It looks like you're just passing an uninitialised pointer.

    – Jonathan Potter
    Nov 21 '18 at 11:28














0












0








0








Node-ffi has lack of documentation



I am trying to use this function https://docs.microsoft.com/en-us/windows/desktop/api/ras/nf-ras-rasenumconnectionsw



const ffi = require( 'ffi-napi' );
const ref = require( 'ref' );

var myobj = ref.types.void;
var myobjPtr = ref.refType( myobj );
var myobjPtrPtr = ref.refType( myobjPtr );
var long1 = ref.refType( 'long' );
var long2 = ref.refType( 'long' );

var firstVar = ref.alloc( myobjPtrPtr );
var longVar1 = ref.alloc( 'long' );
var longVar2 = ref.alloc( 'long' );

let ras = new ffi.Library( 'Rasapi32.dll', {
'RasEnumConnectionsW': [
'long', // Return value - DWORD
[ // Arguments
// Pointer to a buffer that receives, on output, an array of RASCONN structures,
// one for each RAS connection.
myobjPtrPtr, // LPRASCONNW

// Pointer to a variable that, on input, contains the size, in bytes, of the buffer
// specified by lprasconn.
long1, // LPDWORD

// Pointer to a variable that receives the number of RASCONN structures written to
// the buffer specified by lprasconn.
long2 // LPDWORD
]
]
});

ras.RasEnumConnectionsW( firstVar, longVar1, longVar2 );

console.log( ref.deref( firstVar ) );


Right now node-ffi gives be UintArray8. Not array of strings, not array of objects










share|improve this question
















Node-ffi has lack of documentation



I am trying to use this function https://docs.microsoft.com/en-us/windows/desktop/api/ras/nf-ras-rasenumconnectionsw



const ffi = require( 'ffi-napi' );
const ref = require( 'ref' );

var myobj = ref.types.void;
var myobjPtr = ref.refType( myobj );
var myobjPtrPtr = ref.refType( myobjPtr );
var long1 = ref.refType( 'long' );
var long2 = ref.refType( 'long' );

var firstVar = ref.alloc( myobjPtrPtr );
var longVar1 = ref.alloc( 'long' );
var longVar2 = ref.alloc( 'long' );

let ras = new ffi.Library( 'Rasapi32.dll', {
'RasEnumConnectionsW': [
'long', // Return value - DWORD
[ // Arguments
// Pointer to a buffer that receives, on output, an array of RASCONN structures,
// one for each RAS connection.
myobjPtrPtr, // LPRASCONNW

// Pointer to a variable that, on input, contains the size, in bytes, of the buffer
// specified by lprasconn.
long1, // LPDWORD

// Pointer to a variable that receives the number of RASCONN structures written to
// the buffer specified by lprasconn.
long2 // LPDWORD
]
]
});

ras.RasEnumConnectionsW( firstVar, longVar1, longVar2 );

console.log( ref.deref( firstVar ) );


Right now node-ffi gives be UintArray8. Not array of strings, not array of objects







node.js winapi node-ffi






share|improve this question















share|improve this question













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edited Nov 21 '18 at 10:49







Rustam

















asked Nov 21 '18 at 10:06









RustamRustam

1,49911332




1,49911332








  • 1





    You're meant to provide a buffer (of a size that you choose and specify) for the information to be returned in. It looks like you're just passing an uninitialised pointer.

    – Jonathan Potter
    Nov 21 '18 at 11:28














  • 1





    You're meant to provide a buffer (of a size that you choose and specify) for the information to be returned in. It looks like you're just passing an uninitialised pointer.

    – Jonathan Potter
    Nov 21 '18 at 11:28








1




1





You're meant to provide a buffer (of a size that you choose and specify) for the information to be returned in. It looks like you're just passing an uninitialised pointer.

– Jonathan Potter
Nov 21 '18 at 11:28





You're meant to provide a buffer (of a size that you choose and specify) for the information to be returned in. It looks like you're just passing an uninitialised pointer.

– Jonathan Potter
Nov 21 '18 at 11:28












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