Re: Passing Command Line Arguments to a new Thread
On Thu, Aug 07, 2014 at 06:23:24PM +, Nordlöw via Digitalmars-d-learn
wrote:
What is the best way to forward a string[] as argument to a function
called through std.concurrency.spawn().
I need this in the following example where I start the vibe.d event
loop in the main thread (the only way I've managed to get
runEventLoop() to work) and run my other program logic in another
which requires command line arguments to passed to the new thread.
void otherMain(string[] args)
{
// use args
}
void main(string[] args)
{
import std.concurrency: spawn;
auto otherMainTid = spawn(otherMain, args); // this line fails
runEventLoop();
}
The line calling spawn() fails as
/home/per/opt/x86_64-unknown-linux-gnu/dmd/linux/bin64/src/phobos/std/concurrency.d(442):
Error: static assert Aliases to mutable thread-local data not allowed.
Maybe try args.idup instead?
T
--
2+2=4. 2*2=4. 2^2=4. Therefore, +, *, and ^ are the same operation.
Re: Passing Command Line Arguments to a new Thread
On Thursday, 7 August 2014 at 18:33:40 UTC, H. S. Teoh via
Digitalmars-d-learn wrote:
On Thu, Aug 07, 2014 at 06:23:24PM +, Nordlöw via
Digitalmars-d-learn wrote:
What is the best way to forward a string[] as argument to a
function
called through std.concurrency.spawn().
I need this in the following example where I start the vibe.d
event
loop in the main thread (the only way I've managed to get
runEventLoop() to work) and run my other program logic in
another
which requires command line arguments to passed to the new
thread.
void otherMain(string[] args)
{
// use args
}
void main(string[] args)
{
import std.concurrency: spawn;
auto otherMainTid = spawn(otherMain, args); // this line
fails
runEventLoop();
}
The line calling spawn() fails as
/home/per/opt/x86_64-unknown-linux-gnu/dmd/linux/bin64/src/phobos/std/concurrency.d(442):
Error: static assert Aliases to mutable thread-local data
not allowed.
Maybe try args.idup instead?
But this shouldn't be necessary, right? It's a mutable slice to
immutable data, but the slice is passed by value, so no mutable
sharing takes place.
Re: Passing Command Line Arguments to a new Thread
On Thursday, 7 August 2014 at 18:38:37 UTC, Marc Schütz wrote:
But this shouldn't be necessary, right? It's a mutable slice to
immutable data, but the slice is passed by value, so no mutable
sharing takes place.
I agree.
I'll use .idup anyhow. For this work I however have to do
void otherMain(immutable string[] args)
{
useArgs(args.dup);
}
as my function useArgs has signature
useArgs(string[] args)
Seems awkward.
Re: Passing Command Line Arguments to a new Thread
On Thursday, 7 August 2014 at 18:38:37 UTC, Marc Schütz wrote: But this shouldn't be necessary, right? It's a mutable slice to immutable data, but the slice is passed by value, so no mutable sharing takes place. The elements of the slice itself are mutable, you can e.g. assign some other string to args[1], which would be a potentially racy change among all threads which share that slice. Only the information start address of slice and length of slice are copied by value, which doesn't protect from this. To be able to share the slice, it would need to be typed as immutable(string)[] instead.
Re: Passing Command Line Arguments to a new Thread
On 2014-08-07 20:23, Nordlöw wrote: What is the best way to forward a string[] as argument to a function called through std.concurrency.spawn(). What about just accessing core.runtime.Runtime.args from the new thread? -- /Jacob Carlborg
Re: Passing Command Line Arguments to a new Thread
On Thursday, 7 August 2014 at 18:23:26 UTC, Nordlöw wrote:
What is the best way to forward a string[] as argument to a
function called through std.concurrency.spawn().
I need this in the following example where I start the vibe.d
event loop in the main thread (the only way I've managed to get
runEventLoop() to work) and run my other program logic in
another which requires command line arguments to passed to the
new thread.
void otherMain(string[] args)
{
// use args
}
void main(string[] args)
{
import std.concurrency: spawn;
auto otherMainTid = spawn(otherMain, args); // this line
fails
runEventLoop();
}
The line calling spawn() fails as
/home/per/opt/x86_64-unknown-linux-gnu/dmd/linux/bin64/src/phobos/std/concurrency.d(442):
Error: static assert Aliases to mutable thread-local data not
allowed.
If you don't care how you get the args to otherMain, you can also
use Runtime.args. That way you wouldn't even need to pass it to
the function in the first place.
http://dlang.org/phobos/core_runtime.html#.Runtime.args
Re: Passing Command Line Arguments to a new Thread
On Thursday, 7 August 2014 at 19:08:37 UTC, Johannes Blume wrote: On Thursday, 7 August 2014 at 18:38:37 UTC, Marc Schütz wrote: But this shouldn't be necessary, right? It's a mutable slice to immutable data, but the slice is passed by value, so no mutable sharing takes place. The elements of the slice itself are mutable, you can e.g. assign some other string to args[1], which would be a potentially racy change among all threads which share that slice. Only the information start address of slice and length of slice are copied by value, which doesn't protect from this. To be able to share the slice, it would need to be typed as immutable(string)[] instead. Ah, indeed. It's mutable ref to mutable ref to immutable data.
