Re: Passing string literals to C

[John Colvin via Digitalmars-d-learn]

On Wednesday, 31 December 2014 at 11:45:33 UTC, Mike Parker wrote:
On 12/31/2014 8:19 PM, Laeeth Isharc wrote:
Argh - no way to edit.
What's best practice here?

D strings are not null-terminated.
===
cpling.c

char* cpling(char *s)
{
  s[0]='!';
  return s;
}
===
dcaller.d

extern(C) char* cpling(char* s);

void callC()
{
  writefln("%s",fromStringz(cpling("hello\0")));
}

or

void callC()
{
  writefln("%s",fromStringz(cpling(toStringz("hello"))));
}

===

am I missing a better way to do this?

String literals are always null-terminated. You can typically 
pass them as-is and D will do the right thing (you can also 
pass "MyStr".ptr if you want).

String literals can implicitly convert to const(char)* or 
immutable(char)*. Neat. It doesn't appear to apply to array 
literals in general though...