Hey guys!
Today while browsing std.string, I read this:
Important Note: When passing a char* to a C function, and the C
function keeps it around for any reason, make sure that you keep
a reference to it in your D code. Otherwise, it may go away
during a garbage collection cycle and cause a nasty bug when the
C code tries to use it.
Good to know! Now, I have seen things like this before.
extern (C) void someCFunction(const(char)* stuff);
void main()
{
someCFunction("string!");
}
I know that string literals implicitly cast to this type and even
have the '\0' at the end, but couldn't this cause the bug
described above?
I'm currently working on a port of a C library into D, so I'm
trying to have the end user avoid using pointers all together. I
might write the above code as something like:
void someFunction(string stuff)
{
stuff ~= "\0";
someCFunction(stuff.ptr);
}
But that was before I read the warning! Obviously if I know 100%
that the C function doesn't keeps a copy of this pointer the
above would be ok to do. I already had some ideas on how to deal
with this, but I was wondering what other people have done. Do
you just make some place holder string variable to make sure it
won't get GC'd? Or is there a more elegant way?
