Re: OT: What causes the Segfault in the following?

[Andrew Edwards via Digitalmars-d-learn]

Ali Çehreli wrote:
On 08/03/2017 06:02 PM, Andrew Edwards wrote:
    char *s;

That's an uninitialized C string.

OK, I was is indeed the problem. I was thinking for some reason that s 
gets initialized inside nk_color_hex_rgb() but it's expecting to an 
array to work with. I actually noticed that couldn't, for the life of 
me, associate it to the cause of the resulting issue.


    nk_color_hex_rgb(s, str);

That function is expecting it to have at least 7 chars when doing things
like

    output[1] = (char)NK_TO_HEX((col.r & 0x0F));

So you have to have a proper pointer to the first element of an array to
pass to nk_color_hex_rgb. The following may work but you shouldn't be
needing to use magic constants like 7:
    char[7] s;
    nk_color_hex_rgb(s.ptr, str);
    // ...
    printf("%s\n", s.ptr);

got you... this makes sense, but I'm doing it differently in D. See my 
response to Steven. I was only experiencing this issue in C.

There's probably the proper C macro that defines it so that you can do

  char[BLAH_LENGTH] s:

Ali


Much appreciated.