embedded python and interpreter threads

[Charlie DeTar]

So, I have an amazing, functioning foobar class that embeds python.
Only trouble is, I want to be able to have multiple foobar objects at
once, each with their own interpreters, stdouts, and stderrs.

My initialization of the python interpreter in the class "x" is as follows:
[snip]
if (!Py_IsInitiali zed()) {
PyEval_InitThre ads();
Py_Initialize() ;
}

// Start and switch to a new interpreter thread.
x->thread = Py_NewInterpret er();

// initialize the module 'logMethods', defined elsewhere,
// which contains my stdout and stderr definitions
Py_InitModule(" log", logMethods);

// overwrite Python's stdout and stderr
PyRun_SimpleStr ing(
"import log\n"
"import sys\n"
"class StdoutCatcher:\ n"
"\tdef write(self, str):\n"
"\t\t.CaptureSt dout(str)\n"
"class StderrCatcher:\ n"
"\tdef write(self, str):\n"
"\t\t.CaptureSt derr(str)\n"
"sys.stdout = StdoutCatcher() \n"
"sys.stderr = StderrCatcher() \n");

PyEval_ReleaseT hread(x->thread);
[snip]

Everything seems to work as expected - each object seems to have its own
interpreter (if I evaluate "tree = 'a larch'" in one of them, 'tree' is
not thusly defined in the others). Since I store the threadstate as a
property of the object, I can easily juggle the interpreter lock between
objects when evaluating python code. However, the last foobar object to
be instantiated collects the stdout and stderr of all the other objects
(as though the stdout and stderr definitions were shared over all the
objects). This seems strange, as the docs say that if I start a
"Py_NewInterpre ter()" I get new copies of all the modules, particuarly
'sys', and explicitly 'stdout' and 'stderr'.

I thought of the possibility that the 'logMethods' structure which
includes my versions of stdout and stderr might be behaving statically.
But I didn't define it as static... I am new to C, so there might be
something basic I am missing. Any suggestions or ideas?

Thanks,
Charlie DeTar

[Charlie DeTar]

Re: embedded python and interpreter threads

Quick correction, sorry - the command should read like this (I had
omitted the "log" before 'CaptureStdout' and 'CaptureStderr' ). Same
problems exist.

PyRun_SimpleStr ing(
"import log\n"
"import sys\n"
"class StdoutCatcher:\ n"
"\tdef write(self, str):\n"
"\t\tlog.Captur eStdout(str)\n"
"class StderrCatcher:\ n"
"\tdef write(self, str):\n"
"\t\tlog.Captur eStderr(str)\n"
"sys.stdout = StdoutCatcher() \n"
"sys.stderr = StderrCatcher() \n");

=Charlie

Charlie DeTar wrote:[color=blue]
> So, I have an amazing, functioning foobar class that embeds python. Only
> trouble is, I want to be able to have multiple foobar objects at once,
> each with their own interpreters, stdouts, and stderrs.
>
> My initialization of the python interpreter in the class "x" is as follows:
> [snip]
> if (!Py_IsInitiali zed()) {
> PyEval_InitThre ads();
> Py_Initialize() ;
> }
>
> // Start and switch to a new interpreter thread.
> x->thread = Py_NewInterpret er();
>
> // initialize the module 'logMethods', defined elsewhere,
> // which contains my stdout and stderr definitions
> Py_InitModule(" log", logMethods);
>
> // overwrite Python's stdout and stderr
> PyRun_SimpleStr ing(
> "import log\n"
> "import sys\n"
> "class StdoutCatcher:\ n"
> "\tdef write(self, str):\n"
> "\t\t.CaptureSt dout(str)\n"
> "class StderrCatcher:\ n"
> "\tdef write(self, str):\n"
> "\t\t.CaptureSt derr(str)\n"
> "sys.stdout = StdoutCatcher() \n"
> "sys.stderr = StderrCatcher() \n");[/color]

[Charlie DeTar]

Re: embedded python and interpreter threads

Woohoo, fixed my problem. It had to do with the way I was handling the
methods which overwrote stderr and stdout. Yeehaw!

=Charlie


Charlie DeTar wrote:[color=blue]
> Quick correction, sorry - the command should read like this (I had
> omitted the "log" before 'CaptureStdout' and 'CaptureStderr' ). Same
> problems exist.
>
> PyRun_SimpleStr ing(
> "import log\n"
> "import sys\n"
> "class StdoutCatcher:\ n"
> "\tdef write(self, str):\n"
> "\t\tlog.Captur eStdout(str)\n"
> "class StderrCatcher:\ n"
> "\tdef write(self, str):\n"
> "\t\tlog.Captur eStderr(str)\n"
> "sys.stdout = StdoutCatcher() \n"
> "sys.stderr = StderrCatcher() \n");
>
> =Charlie
>
> Charlie DeTar wrote:
>[color=green]
>> So, I have an amazing, functioning foobar class that embeds python.
>> Only trouble is, I want to be able to have multiple foobar objects at
>> once, each with their own interpreters, stdouts, and stderrs.
>>
>> My initialization of the python interpreter in the class "x" is as
>> follows:
>> [snip]
>> if (!Py_IsInitiali zed()) {
>> PyEval_InitThre ads();
>> Py_Initialize() ;
>> } // Start and switch to a new interpreter thread.
>> x->thread = Py_NewInterpret er();
>>
>> // initialize the module 'logMethods', defined elsewhere,
>> // which contains my stdout and stderr definitions
>> Py_InitModule(" log", logMethods);
>> // overwrite Python's stdout and stderr
>> PyRun_SimpleStr ing(
>> "import log\n"
>> "import sys\n"
>> "class StdoutCatcher:\ n"
>> "\tdef write(self, str):\n"
>> "\t\t.CaptureSt dout(str)\n"
>> "class StderrCatcher:\ n"
>> "\tdef write(self, str):\n"
>> "\t\t.CaptureSt derr(str)\n"
>> "sys.stdout = StdoutCatcher() \n"
>> "sys.stderr = StderrCatcher() \n");[/color][/color]