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Do I need to memset a C struct in Swift?

AFAIK, In swift, calling the default initialiser of classes/structs will initialise everything to 0 , nil. In C (socket programming for example) sometimes memset is used to set everything to 0 before using the struct. Do I need to use memset in swift too or is fine the way I wrote it?

(BTW, In this case memset is used because hints should be set to 0 except below 2 parameters. Non 0 (garbage, etc) will have side effects on res when calling getaddrinfo.

C:

struct addrinfo hints, *res;
int status;

memset(&hints, 0, sizeof hints);
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;

status = getaddrinfo(NULL, MYPORT, &hints, &res);

Swift:

var res = UnsafeMutablePointer<addrinfo>()
var hints = addrinfo()
hints.ai_family = AF_UNSPEC
hints.ai_socktype = SOCK_STREAM

let status = getaddrinfo(nil, MYPORT, &hints, &res)
like image 590
nacho4d Avatar asked Dec 20 '22 02:12

nacho4d


1 Answers

From the Xcode 6.3 release notes:

Imported C structs now have a default initializer in Swift that initializes all of the struct's fields to zero.

which means that

var hints = addrinfo()

initializes all fields of struct addrinfo to zero and there is no need to call memset().

like image 128
Martin R Avatar answered Jan 11 '23 20:01

Martin R