Some "safe" languages like Swift and Go offer "unsafe" pointers for use with APIs written in languages like C and Objective-C. Questions using this tag should also have the relevant language tag, e.g. [swift] or [go].
Questions tagged [unsafe-pointers]
250 questions
0
votes
0 answers
Preparing for Swift 4 - UnsafeMutablePointer migration to UnsafeMutableBufferPointer
I've got a char-by-char function that returns a character from a file. It is pretty performant, as far as i now.
Xcode says that the characterPointer.initialize(from: s.characters) "will be removed in Swift 4.0." And I have to "use…
Peter Shaw
- 1,867
- 1
- 19
- 32
0
votes
1 answer
From NSTextfield to (const unsigned char *) with Swift
How can i properly received a (const unsigned char *) in a C program from a NSTextField in Swift ?
Case 1 :
let string1 = atextfield!.stringValue // -> "Test"
print(string1) // -> "Test"
string1/_core/_baseAddress = nil // in debug
let string2 =…
Stephane
- 391
- 1
- 2
- 13
0
votes
0 answers
How to pass image data to Swift MagicWand?
The read() API accept data type but how does this read data?
https://github.com/naithar/MagickWand/blob/master/Sources/MagickWand/Wand/ImageWand/ImageWand%2BRead.swift#L51
let urlImage:URL? = URL(fileURLWithPath: "files/test.png")
do {
…
James Lei
- 340
- 2
- 5
- 15
0
votes
1 answer
Swift dictionary doesn't want to populate from C Callback function
I'm writing a PDF Parser in Swift and I've reached the point where I get all the font data with a callback function (CGPDFDictionaryApplyFunction), the getFont function is supposed to populate the fonts dictionary in the PDFFontCollection…
Michael Schmid
- 15
- 4
0
votes
0 answers
Can not initialize UnsafePointer
I am trying to initialize an unsafe pointer
func f1()
{
var ifaddr : UnsafeMutablePointer?
// ....
// .... collect ifaddr value
var d1 = UnsafePointer(ifaddr)
}
and received the below error in the last line…
GeorgeKalash
- 1
- 1
0
votes
1 answer
Convert CUnsignedChar pointer to CChar pointer
I have an objective C function that gives me a
UnsafePointer/UnsafePointer.
However I need this data as a
UnsafePointer
unfortunately the function I require doesn't take
UnsafePointer.
Michael Schmid
- 15
- 4
0
votes
1 answer
How do I update a statement of Data of UnsafePointer for Swift 3?
I'm getting the error below for this statement:
let data = Data(bytes: UnsafePointer(cubeData), count: cubeData.count * MemoryLayout.size)
cubeData is defined as: var cubeData = [Float](repeating: 0, count: size * size * size *…
ICL1901
- 7,632
- 14
- 90
- 138
0
votes
2 answers
Error in UnsafeMutablePointer in swift3
My codd look like this
let samples = UnsafeMutableBufferPointer(start:UnsafeMutablePointer(buffer.mData), count: Int(buffer.mDataByteSize)/sizeof(Int16))
While running this code is generating the following error
Cannot invoke initializer for…
Sachin
- 135
- 9
0
votes
1 answer
NSMutableData's bytes to UnsafeMutableRawPointer not updating the value of mutableData
I am having a struct object. And a method, whose input is payload. Now I am creating a mutableData named packet, and it's mutable bytes are referring to ICMPHeader struct.
struct ICMPHeader {
var type:UInt8
var code:UInt8
var…
Ankit Thakur
- 4,739
- 1
- 19
- 35
0
votes
0 answers
Data, UnsafeMutablePointer and extended attributes in Swift 3
In swift 2 I had an NSURL extension for working with extended attributes and it included this:
func setAttribute(name: String, value: String) {
let data = value.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false)!
…
dbmrq
- 1,451
- 13
- 32
0
votes
1 answer
Using C in Swift - strlcpy - Cannot convert value of type 'UnsafeMutablePointer<_>'
I am trying to use strlcpy in Swift 3.0, but keep getting the error "Cannot convert value of type 'UnsafeMutablePointer<_>' to expected argument type 'UnsafeMutablePointer!'"
Here is my code
func login(portal: String, username: String, password:…
Lneuner
- 1,090
- 1
- 9
- 19
0
votes
1 answer
Casting UnsafeMutablePointers to UnsafeMutableRawPointers
I have a couple of issues updating to swift 3.0. I have the following code:
// Retrieve the Device GUID
let device = UIDevice.current
let uuid = device.identifierForVendor
let mutableData = NSMutableData(length: 16)
…
Tom
- 790
- 2
- 9
- 32
0
votes
1 answer
Idiomatic way in Swift to typecast an UnsafeMutablePointer to an Array of non-void types?
Many C/Obj-C APIs deal in pointers to void. In swift, these types are typically represented as UnsafeMutablePointer or UnsafePointer (for const void*). What is the typical way in Swift to reinterpret these values to a packed array of data, such as…
Fooberman
- 626
- 5
- 14
0
votes
1 answer
copy NSData to UnsafeMutablePointer
Hi there stackoverflowers. I'm implementing a wrapper for Secure Transport and I'm stuck on some of the C -> Swift syntax.
func sslReadCallback(connection: SSLConnectionRef,
data: UnsafeMutablePointer,
var dataLength:…
Mike S
- 4,092
- 5
- 35
- 68
0
votes
1 answer
How to write an unsafepointer of type float in MPSImageDilate
I am new to Unsafepointer. In the following in this documentation, it says I need the values to be of type Unsafepointer. I need it to be equivalent of Array of 139*139 elements of repeatedValues of 1.0 (floating number).…
Nasiba
- 321
- 2
- 15