Re: How to use C code in D
On Thursday, 23 March 2017 at 18:10:20 UTC, Dillen Meijboom wrote: Hi there, I'm learning D for a while because it's really easy to use C-code in D. The problem is that I don't really get how to deal with the data structures defined in C in D. Perhaps, it will be interesting to you. I advise to look at https://www.youtube.com/watch?v=HTgJaRRfLPk
Re: How to use C code in D
On Thursday, 23 March 2017 at 18:10:20 UTC, Dillen Meijboom wrote: Hi there, I'm learning D for a while because it's really easy to use C-code in D. The problem is that I don't really get how to deal with the data structures defined in C in D. D makes it easy to utilize C code, but there is no magic C to D wrapper. There are some functions in Phobos which help (e.g. toStringz). You can slice a C string to utilize it as a slice, but usually there are ownership issue with this approach. In my experience, you'll be writing some C style code to provide a D interface.
Re: How to use C code in D
On Thursday, 23 March 2017 at 18:10:20 UTC, Dillen Meijboom wrote:
Hi there,
I'm learning D for a while because it's really easy to use
C-code in D.
The problem is that I don't really get how to deal with the
data structures defined in C in D.
At one time for instance I've tried to get all environment
variables on a POSIX system. I succeeded but I think it can be
done way easier.
So my question basically is:
1. How can I learn to use C code in D? Is there any good
tutorial or other packages that deal with this a lot?
2. Is the way I'm currently doing it okay or is it wrong and do
I need to do something else?
As a reference, I'm currently using the following D code to get
all environment variables:
```
import std.array;
import std.conv: to;
import std.string: fromStringz;
extern (C) extern const char** environ;
string[string] getenv() {
string[string] env;
char* line;
for (auto data = cast(char**)environ; (line = *data) != null;
++data) {
auto keyval = to!string(fromStringz(line)).split('=');
env[keyval[0]] = keyval[1];
}
return env;
}
```
https://dlang.org/phobos/std_process.html#.environment means it's
already done for you.
C global variables are __gshared.
Reading other people's source code - starting with standard
library and maybe look at some of the bindings and wrappers on
code.dlang.org.
IRC chat to get a quick answer most of the time.
How to use C code in D
Hi there,
I'm learning D for a while because it's really easy to use C-code
in D.
The problem is that I don't really get how to deal with the data
structures defined in C in D.
At one time for instance I've tried to get all environment
variables on a POSIX system. I succeeded but I think it can be
done way easier.
So my question basically is:
1. How can I learn to use C code in D? Is there any good tutorial
or other packages that deal with this a lot?
2. Is the way I'm currently doing it okay or is it wrong and do I
need to do something else?
As a reference, I'm currently using the following D code to get
all environment variables:
```
import std.array;
import std.conv: to;
import std.string: fromStringz;
extern (C) extern const char** environ;
string[string] getenv() {
string[string] env;
char* line;
for (auto data = cast(char**)environ; (line = *data) != null;
++data) {
auto keyval = to!string(fromStringz(line)).split('=');
env[keyval[0]] = keyval[1];
}
return env;
}
```
