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digitalmars.D - Calling D from C

reply "Chris W." <wendlec cd.ie> writes:
I have a problem when calling D functions from C. While I can
perform simple arithmetic operations (i.e. the calculation is
performed in D and returned to C), I experience problems when
trying to perform string/char operations or call functions from
the D standard library (e.g. writefln()). The usual error message
I get is either "Bus error" or "Segmentation fault". I haven't
been able to find the reason for this. The programs compile and
link, however, when run, they terminate with "Bus error" whenever
a D function is performed within the D code, e.g. something like
char[] s2 = s.dup; (s is a char* passed from C). Any hint or help
would be appreciated.

I am using Mac OS X, 10.6.7
Mar 12 2012
next sibling parent =?UTF-8?B?QWxleCBSw7hubmUgUGV0ZXJzZW4=?= <xtzgzorex gmail.com> writes:
On 12-03-2012 15:53, Chris W. wrote:

 I have a problem when calling D functions from C. While I can
 perform simple arithmetic operations (i.e. the calculation is
 performed in D and returned to C), I experience problems when
 trying to perform string/char operations or call functions from
 the D standard library (e.g. writefln()). The usual error message
 I get is either "Bus error" or "Segmentation fault". I haven't
 been able to find the reason for this. The programs compile and
 link, however, when run, they terminate with "Bus error" whenever
 a D function is performed within the D code, e.g. something like
 char[] s2 = s.dup; (s is a char* passed from C). Any hint or help
 would be appreciated.

 I am using Mac OS X, 10.6.7


Are you remembering to initialize the runtime, attach your thread, 
etc... Also, you can't call D functions directly from C code. You have 
to go through an extern (C) wrapper that then calls the D function.

-- 
- Alex
Mar 12 2012
prev sibling parent reply "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Mon, 12 Mar 2012 10:53:09 -0400, Chris W. <wendlec cd.ie> wrote:


 I have a problem when calling D functions from C. While I can
 perform simple arithmetic operations (i.e. the calculation is
 performed in D and returned to C), I experience problems when
 trying to perform string/char operations or call functions from
 the D standard library (e.g. writefln()). The usual error message
 I get is either "Bus error" or "Segmentation fault". I haven't
 been able to find the reason for this. The programs compile and
 link, however, when run, they terminate with "Bus error" whenever
 a D function is performed within the D code, e.g. something like
 char[] s2 = s.dup; (s is a char* passed from C). Any hint or help
 would be appreciated.

 I am using Mac OS X, 10.6.7


If C is running your application startup, you must initialize D's runtime  
 from your C main routine.

-Steve
Mar 12 2012
parent reply "Chris W." <wendlec tcd.ie> writes:
On Monday, 12 March 2012 at 15:00:31 UTC, Steven Schveighoffer 
wrote:

 On Mon, 12 Mar 2012 10:53:09 -0400, Chris W. <wendlec cd.ie> 
 wrote:


 I have a problem when calling D functions from C. While I can
 perform simple arithmetic operations (i.e. the calculation is
 performed in D and returned to C), I experience problems when
 trying to perform string/char operations or call functions from
 the D standard library (e.g. writefln()). The usual error 
 message
 I get is either "Bus error" or "Segmentation fault". I haven't
 been able to find the reason for this. The programs compile and
 link, however, when run, they terminate with "Bus error" 
 whenever
 a D function is performed within the D code, e.g. something 
 like
 char[] s2 = s.dup; (s is a char* passed from C). Any hint or 
 help
 would be appreciated.

 I am using Mac OS X, 10.6.7


 If C is running your application startup, you must initialize 
 D's runtime from your C main routine.

 -Steve


Yes, I am using extern (C) and in my C main function I call

gc_init();
thread_attachThis();

This works fine for primitive types such as int + int 
calculations. But anything more sophisticated renders a Bus 
error. I am sure it is just some little detail I have forgotten.
Mar 12 2012
parent reply =?UTF-8?B?QWxleCBSw7hubmUgUGV0ZXJzZW4=?= <xtzgzorex gmail.com> writes:
On 12-03-2012 16:09, Chris W. wrote:

 On Monday, 12 March 2012 at 15:00:31 UTC, Steven Schveighoffer wrote:

 On Mon, 12 Mar 2012 10:53:09 -0400, Chris W. <wendlec cd.ie> wrote:


 I have a problem when calling D functions from C. While I can
 perform simple arithmetic operations (i.e. the calculation is
 performed in D and returned to C), I experience problems when
 trying to perform string/char operations or call functions from
 the D standard library (e.g. writefln()). The usual error message
 I get is either "Bus error" or "Segmentation fault". I haven't
 been able to find the reason for this. The programs compile and
 link, however, when run, they terminate with "Bus error" whenever
 a D function is performed within the D code, e.g. something like
 char[] s2 = s.dup; (s is a char* passed from C). Any hint or help
 would be appreciated.

 I am using Mac OS X, 10.6.7


 If C is running your application startup, you must initialize D's
 runtime from your C main routine.

 -Steve


 Yes, I am using extern (C) and in my C main function I call

 gc_init();
 thread_attachThis();

 This works fine for primitive types such as int + int calculations. But
 anything more sophisticated renders a Bus error. I am sure it is just
 some little detail I have forgotten.


Don't forget to call this: 
https://github.com/D-Programming-Language/druntime/blob/master/src/core/runtime.d#L33

Documented here: 
https://github.com/D-Programming-Language/druntime/blob/master/src/core/runtime.d#L101

-- 
- Alex
Mar 12 2012
next sibling parent "Chris W." <wendlec tcd.ie> writes:
On Monday, 12 March 2012 at 15:17:32 UTC, Alex Rønne Petersen 
wrote:

 On 12-03-2012 16:09, Chris W. wrote:

 On Monday, 12 March 2012 at 15:00:31 UTC, Steven Schveighoffer 
 wrote:

 On Mon, 12 Mar 2012 10:53:09 -0400, Chris W. <wendlec cd.ie> 
 wrote:


 I have a problem when calling D functions from C. While I can
 perform simple arithmetic operations (i.e. the calculation is
 performed in D and returned to C), I experience problems when
 trying to perform string/char operations or call functions 
 from
 the D standard library (e.g. writefln()). The usual error 
 message
 I get is either "Bus error" or "Segmentation fault". I 
 haven't
 been able to find the reason for this. The programs compile 
 and
 link, however, when run, they terminate with "Bus error" 
 whenever
 a D function is performed within the D code, e.g. something 
 like
 char[] s2 = s.dup; (s is a char* passed from C). Any hint or 
 help
 would be appreciated.

 I am using Mac OS X, 10.6.7


 If C is running your application startup, you must initialize 
 D's
 runtime from your C main routine.

 -Steve


 Yes, I am using extern (C) and in my C main function I call

 gc_init();
 thread_attachThis();

 This works fine for primitive types such as int + int 
 calculations. But
 anything more sophisticated renders a Bus error. I am sure it 
 is just
 some little detail I have forgotten.


 Don't forget to call this: 
 https://github.com/D-Programming-Language/druntime/blob/master/src/core/runtime.d#L33

 Documented here: 
 https://github.com/D-Programming-Language/druntime/blob/master/src/core/runtime.d#L101


Thanks a million, calling rt_init(); in my C code did the trick. 
Now I can perform string operations etc. I knew it was just a 
tiny little detail.
Mar 12 2012
prev sibling parent reply "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Mon, 12 Mar 2012 11:17:31 -0400, Alex R=C3=B8nne Petersen  =

<xtzgzorex gmail.com> wrote:


 On 12-03-2012 16:09, Chris W. wrote:

 On Monday, 12 March 2012 at 15:00:31 UTC, Steven Schveighoffer wrote:=





 On Mon, 12 Mar 2012 10:53:09 -0400, Chris W. <wendlec cd.ie> wrote:


 I have a problem when calling D functions from C. While I can
 perform simple arithmetic operations (i.e. the calculation is
 performed in D and returned to C), I experience problems when
 trying to perform string/char operations or call functions from
 the D standard library (e.g. writefln()). The usual error message
 I get is either "Bus error" or "Segmentation fault". I haven't
 been able to find the reason for this. The programs compile and
 link, however, when run, they terminate with "Bus error" whenever
 a D function is performed within the D code, e.g. something like
 char[] s2 =3D s.dup; (s is a char* passed from C). Any hint or help=









 would be appreciated.

 I am using Mac OS X, 10.6.7


 If C is running your application startup, you must initialize D's
 runtime from your C main routine.

 -Steve


 Yes, I am using extern (C) and in my C main function I call

 gc_init();
 thread_attachThis();

 This works fine for primitive types such as int + int calculations. B=




ut

 anything more sophisticated renders a Bus error. I am sure it is just=





 some little detail I have forgotten.


 Don't forget to call this:  =



 https://github.com/D-Programming-Language/druntime/blob/master/src/cor=


e/runtime.d#L33

 Documented here:  =



 https://github.com/D-Programming-Language/druntime/blob/master/src/cor=


e/runtime.d#L101

More appropriate:

http://dlang.org/phobos/core_runtime.html#initialize

And actually, I think this should do everything necessary.  No need to  =

call gc_init and thread_attachThis().

-Steve
Mar 12 2012
next sibling parent reply "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Mon, 12 Mar 2012 11:36:45 -0400, Steven Schveighoffer  =

<schveiguy yahoo.com> wrote:


 On Mon, 12 Mar 2012 11:17:31 -0400, Alex R=C3=B8nne Petersen  =



 <xtzgzorex gmail.com> wrote:


 On 12-03-2012 16:09, Chris W. wrote:

 On Monday, 12 March 2012 at 15:00:31 UTC, Steven Schveighoffer wrote=






:

 On Mon, 12 Mar 2012 10:53:09 -0400, Chris W. <wendlec cd.ie> wrote:=









 I have a problem when calling D functions from C. While I can
 perform simple arithmetic operations (i.e. the calculation is
 performed in D and returned to C), I experience problems when
 trying to perform string/char operations or call functions from
 the D standard library (e.g. writefln()). The usual error message
 I get is either "Bus error" or "Segmentation fault". I haven't
 been able to find the reason for this. The programs compile and
 link, however, when run, they terminate with "Bus error" whenever
 a D function is performed within the D code, e.g. something like
 char[] s2 =3D s.dup; (s is a char* passed from C). Any hint or hel=










p

 would be appreciated.

 I am using Mac OS X, 10.6.7


 If C is running your application startup, you must initialize D's
 runtime from your C main routine.

 -Steve


 Yes, I am using extern (C) and in my C main function I call

 gc_init();
 thread_attachThis();

 This works fine for primitive types such as int + int calculations. =






But

 anything more sophisticated renders a Bus error. I am sure it is jus=






t

 some little detail I have forgotten.


 Don't forget to call this:  =





 https://github.com/D-Programming-Language/druntime/blob/master/src/co=




re/runtime.d#L33

 Documented here:  =





 https://github.com/D-Programming-Language/druntime/blob/master/src/co=




re/runtime.d#L101

 More appropriate:

 http://dlang.org/phobos/core_runtime.html#initialize

 And actually, I think this should do everything necessary.  No need to=


  =


 call gc_init and thread_attachThis().


Hm... just realized you can't do this, since it's a D function :D

But yeah, all it does is call rt_init, so you should be good.

-Steve
Mar 12 2012
parent reply Stewart Gordon <smjg_1998 yahoo.com> writes:
On 12/03/2012 15:38, Steven Schveighoffer wrote:
<snip>

 http://dlang.org/phobos/core_runtime.html#initialize

 And actually, I think this should do everything necessary. No need to call
gc_init and
 thread_attachThis().


 Hm... just realized you can't do this, since it's a D function :D


Why can't this be dealt with using an extern (C) wrapper function in the D code?

Stewart.
Mar 12 2012
next sibling parent Sean Kelly <sean invisibleduck.org> writes:
On Mar 12, 2012, at 9:54 AM, Stewart Gordon <smjg_1998 yahoo.com> wrote:


 On 12/03/2012 15:38, Steven Schveighoffer wrote:
 <snip>

 http://dlang.org/phobos/core_runtime.html#initialize
=20
 And actually, I think this should do everything necessary. No need to ca=






ll gc_init and

 thread_attachThis().


=20
 Hm... just realized you can't do this, since it's a D function :D


=20
 Why can't this be dealt with using an extern (C) wrapper function in the D=


 code?

D function names are mangled based on the name of the module they're defined=
 in. For the runtime code, it's easier to wrap extern C calls with D functio=
ns.=20=
Mar 12 2012
prev sibling parent "Steven Schveighoffer" <schveiguy yahoo.com> writes:
On Mon, 12 Mar 2012 12:54:25 -0400, Stewart Gordon <smjg_1998 yahoo.com>  
wrote:


 On 12/03/2012 15:38, Steven Schveighoffer wrote:
 <snip>

 http://dlang.org/phobos/core_runtime.html#initialize

 And actually, I think this should do everything necessary. No need to  
 call gc_init and
 thread_attachThis().


 Hm... just realized you can't do this, since it's a D function :D


 Why can't this be dealt with using an extern (C) wrapper function in the  
 D code?


All it does is call the extern(C) rt_init.  It was my bad, if you are in  
D-land, it's definitely better to use Runtime.initialize, but from C, the  
best bet is rt_init.

-Steve
Mar 12 2012
prev sibling parent reply =?UTF-8?B?QWxleCBSw7hubmUgUGV0ZXJzZW4=?= <xtzgzorex gmail.com> writes:
On 12-03-2012 16:36, Steven Schveighoffer wrote:

 On Mon, 12 Mar 2012 11:17:31 -0400, Alex Rønne Petersen
 <xtzgzorex gmail.com> wrote:


 On 12-03-2012 16:09, Chris W. wrote:

 On Monday, 12 March 2012 at 15:00:31 UTC, Steven Schveighoffer wrote:

 On Mon, 12 Mar 2012 10:53:09 -0400, Chris W. <wendlec cd.ie> wrote:


 I have a problem when calling D functions from C. While I can
 perform simple arithmetic operations (i.e. the calculation is
 performed in D and returned to C), I experience problems when
 trying to perform string/char operations or call functions from
 the D standard library (e.g. writefln()). The usual error message
 I get is either "Bus error" or "Segmentation fault". I haven't
 been able to find the reason for this. The programs compile and
 link, however, when run, they terminate with "Bus error" whenever
 a D function is performed within the D code, e.g. something like
 char[] s2 = s.dup; (s is a char* passed from C). Any hint or help
 would be appreciated.

 I am using Mac OS X, 10.6.7


 If C is running your application startup, you must initialize D's
 runtime from your C main routine.

 -Steve


 Yes, I am using extern (C) and in my C main function I call

 gc_init();
 thread_attachThis();

 This works fine for primitive types such as int + int calculations. But
 anything more sophisticated renders a Bus error. I am sure it is just
 some little detail I have forgotten.


 Don't forget to call this:
 https://github.com/D-Programming-Language/druntime/blob/master/src/core/runtime.d#L33


 Documented here:
 https://github.com/D-Programming-Language/druntime/blob/master/src/core/runtime.d#L101


 More appropriate:

 http://dlang.org/phobos/core_runtime.html#initialize


But that's effectively an extern (D) function. That's why I linked to 
rt_init.


 And actually, I think this should do everything necessary. No need to
 call gc_init and thread_attachThis().

 -Steve



-- 
- Alex
Mar 12 2012
parent "Chris W." <wendlec tcd.ie> writes:
On Monday, 12 March 2012 at 15:39:15 UTC, Alex Rønne Petersen 
wrote:

 On 12-03-2012 16:36, Steven Schveighoffer wrote:

 On Mon, 12 Mar 2012 11:17:31 -0400, Alex Rønne Petersen
 <xtzgzorex gmail.com> wrote:


 On 12-03-2012 16:09, Chris W. wrote:

 On Monday, 12 March 2012 at 15:00:31 UTC, Steven 
 Schveighoffer wrote:

 On Mon, 12 Mar 2012 10:53:09 -0400, Chris W. 
 <wendlec cd.ie> wrote:


 I have a problem when calling D functions from C. While I 
 can
 perform simple arithmetic operations (i.e. the calculation 
 is
 performed in D and returned to C), I experience problems 
 when
 trying to perform string/char operations or call functions 
 from
 the D standard library (e.g. writefln()). The usual error 
 message
 I get is either "Bus error" or "Segmentation fault". I 
 haven't
 been able to find the reason for this. The programs 
 compile and
 link, however, when run, they terminate with "Bus error" 
 whenever
 a D function is performed within the D code, e.g. 
 something like
 char[] s2 = s.dup; (s is a char* passed from C). Any hint 
 or help
 would be appreciated.

 I am using Mac OS X, 10.6.7


 If C is running your application startup, you must 
 initialize D's
 runtime from your C main routine.

 -Steve


 Yes, I am using extern (C) and in my C main function I call

 gc_init();
 thread_attachThis();

 This works fine for primitive types such as int + int 
 calculations. But
 anything more sophisticated renders a Bus error. I am sure 
 it is just
 some little detail I have forgotten.


 Don't forget to call this:
 https://github.com/D-Programming-Language/druntime/blob/master/src/core/runtime.d#L33


 Documented here:
 https://github.com/D-Programming-Language/druntime/blob/master/src/core/runtime.d#L101


 More appropriate:

 http://dlang.org/phobos/core_runtime.html#initialize


 But that's effectively an extern (D) function. That's why I 
 linked to rt_init.


 And actually, I think this should do everything necessary. No 
 need to
 call gc_init and thread_attachThis().

 -Steve




It's fine, no need to call gc_init() or thread_attachThis() once 
the runtime is initialized. Thanks guys.
Mar 12 2012