How does a function return an array of indefinite length?

海里的浪

in is an input parameter
out is the output parameter
outlength is also an output parameter and is the length of the out array
void fun (unsigned char * in, unsigned char * out, int outlength)
{


}

Since I don't know the length of out, how do I pass out?

bleakstar

Use the address!

joe2086

use
void fun (unsigned char * in, unsigned char *&out, int&outlength)

海里的浪

void __fastcall TForm1 :: btn4Click (TObject * Sender)
{

char * a = new char [100];
char * b;
fun (a, b);


}
// ------------------------------------------------ ---------------------------
void TForm1 :: fun (char * src, char *&dest)
{
   int n = 3;
   char * a = new char [n]; // When will it be released?
   a [0] = '1';
   a [1] = '2';
   a [2] = '3';
   dest = a;
     
}

xietao405

It will be released when exiting the function,
dest should not return the correct value
Just operate dest directly in the function

redsea198201

Two parameters are returned, one is the address of the array and one is the length of the array.
Or use std :: vector to return your vector, just call size () to get the data length