Calling methods written in Go from a Java or C program
Alexandre Bilger
to load a go written "module/library" into another language like java
or c ?
Ian Lance Taylor
You can already do this from C--provided that your main function is
written in Go.
If you want to have a program whose main function is written in C call
subroutines written in Go, that doesn't work today, but it is possible
to make it work. This is not something the Go team is likely to work
on, though. If somebody else wants to work on it, you would basically
have to have to link in the Go runtime library, and have it start up the
first time a Go function was called. You would have to do something to
make sure that the initializers were run for all imported Go packages.
Any direct interaction between Go and Java is almost surely going to be
via C, one way or another.
In general you may want to consider communicating over a socket.
Ian
Alexander Surma
> In general you may want to consider communicating over a socket.
independent from the location of execution.
(This answer is also valid for the always-recurring "Go and dynamic
linking?" threads)
Surma
chris dollin
> Alexandre Bilger <abi...@gmail.com> writes:
> Any direct interaction between Go and Java is almost surely going to be
> via C, one way or another.
How mad would someone have to be to consider compiling Go into
JVM code?
(Not me, I have enough mad projects already.)
Chris
--
Chris "allusive" Dollin
Evan Shaw
> On 23 July 2010 14:27, Ian Lance Taylor <ia...@google.com> wrote:
>> Alexandre Bilger <abi...@gmail.com> writes:
>> Any direct interaction between Go and Java is almost surely going to be
>> via C, one way or another.
>
> How mad would someone have to be to consider compiling Go into
> JVM code?
I think it's more likely that Go code would be called through the JNI
somehow. Compiling Go to JVM bytecode definitely involves a number of
difficulties with relatively few benefits.
- Evan
Alexandre Bilger
calling it from java through JNI
this kind of functionality would permit migrating large codebase from
one language to go incrementaly over time
thanks for your answers
Alex
On Jul 23, 3:52 pm, Evan Shaw <chicken...@gmail.com> wrote:
> On Fri, Jul 23, 2010 at 8:40 AM, chris dollin <ehog.he...@googlemail.com> wrote:
> > On 23 July 2010 14:27, Ian Lance Taylor <i...@google.com> wrote:
David Klaffenbach
go.
Is there something comparable to python's ctypes?
Ian Lance Taylor
David Klaffenbach
roadmap at least.
I've been using cytpes in python recently for accessing functions in
dlls on windows and was wondering how I'd do the same with go.
jimt
bindings) interact with shared c-libraries using Cgo. It'll probably
be easiest to just have a look at the source for some of them.
brainman
> I've been using cytpes in python recently for accessing functions in
> dlls on windows and was wondering how I'd do the same with go.
http://golang.org/src/pkg/syscall/syscall_windows.go:
package main
import (
"syscall"
)
func abort(funcname string, err int) {
panic(funcname + " failed: " + syscall.Errstr(err))
}
func print_version(v uint32) {
major := byte(v)
minor := uint8(v >> 8)
build := uint16(v >> 16)
print("windows version ", major, ".", minor, " (Build ", build, ")
\n")
}
func main() {
h, err := syscall.LoadLibrary("kernel32.dll")
if err != 0 {
abort("LoadLibrary", err)
}
defer syscall.FreeLibrary(h)
proc, err := syscall.GetProcAddress(h, "GetVersion")
if err != 0 {
abort("GetProcAddress", err)
}
r, _, _ := syscall.Syscall(uintptr(proc), 0, 0, 0)
print_version(uint32(r))
}
I haven't tried building it, but it looks ok to me.
Alex
Cory Mainwaring
Ian Lance Taylor
> Thanks Ian. I'd missed cgo's existence, and it appears swig is on the
> roadmap at least.
SWIG is working and the patches have all been contributed back to the
SWIG sources. There has not been a SWIG release since the patches were
contributed, though.
Ian
David/Jones
Why not some awesome IPC?
I really think IPC is the FFI of the future.
It surely would require more thinking, though...