logo
down
shadow

Python ctypes and dynamic linking


Python ctypes and dynamic linking

By : user3863522
Date : January 02 2021, 06:48 AM
may help you . OK, thanks for your help.
to get this to work I had to include the dependencies when linking (duh). I had tried this before but got an error, so solve this I had to recompile fftw with '-fpic' as a CPP flag. all works now.
code :


Share : facebook icon twitter icon
Python ctypes not loading dynamic library on Mac OS X

Python ctypes not loading dynamic library on Mac OS X


By : Weller Miranda
Date : March 29 2020, 07:55 AM
around this issue Nope. As the error message says, there's an architecture mismatch between your python and librepeater.dylib file. Use file to check what the architecture of librepeater.dylib is; your python is going to be built using one of the ones not listed.
Python and C interop: Dynamic resizing of ctypes

Python and C interop: Dynamic resizing of ctypes


By : user4221882
Date : March 29 2020, 07:55 AM
help you fix your problem Here's an example of what we were discussing. This code expects the caller to allocate the buffer.
Test code (Windows)
code :
// IN: test=pre-allocated buffer.
// IN: size=size of pre-allocated buffer.
// RETURNS: 0 and size set to required size.
//          1 and size set to size used.
__declspec(dllexport) int testout(void *pdata, int *psize)
{
    unsigned char * p = (unsigned char *)pdata;

    if (*psize < 5)
    {
        *psize = 5; // set size required
        return 0;  // fail
    }

    p[0] = 123;
    p[1] = 255;
    p[2] = 237;
    p[3] = 12;
    p[4] = 222;
    *psize = 5; // indicate size used

    return 1;  // pass
}
from ctypes import *

test = CDLL('test')
size = c_int(0)
test.testout.argtypes=[c_void_p,POINTER(c_int)]
print "Result of NULL pointer and zero size:",test.testout(None,byref(size))
print "Returned size:",size.value
mem = (c_ubyte * 2)()
size = c_int(sizeof(mem))
print "sizeof(mem):",size.value
print "Result of small buffer:",test.testout(byref(mem),byref(size))
print "Returned size:",size.value
mem = (c_ubyte * size.value)()
print "Result of exact size buffer:",test.testout(byref(mem),byref(size))
print "Returned size:",size.value
for i in range(size.value):
    print mem[i]
mem = (c_ubyte * 20)()
size = c_int(20)
print "Result of bigger buffer:",test.testout(byref(mem),byref(size))
print "Returned size:",size.value
for i in range(size.value):
    print mem[i]
Result of NULL pointer and zero size: 0
Returned size: 5
sizeof(mem): 2
Result of small buffer: 0
Returned size: 5
Result of exact size buffer: 1
Returned size: 5
123
255
237
12
222
Result of bigger buffer: 1
Returned size: 5
123
255
237
12
222
Wrapping blake hash function C implementation into Python using ctypes module, simple python ctypes testvector script al

Wrapping blake hash function C implementation into Python using ctypes module, simple python ctypes testvector script al


By : Spacy
Date : March 29 2020, 07:55 AM
This might help you At the end of the function BitSequence * bl(char *input), The return value output is a local variable that won't exist after the function exits.
Python Ctypes and FFTW Linking

Python Ctypes and FFTW Linking


By : Yang Gao
Date : March 29 2020, 07:55 AM
I wish this helpful for you On the advice of a coworker I searched for and manually deleted all of the fftw related dlls, then made and installed again using the correct flags -fpic. It seems the fftw uninstall script does not completely remove previous versions of fftw.
ctypes Python dynamic function call

ctypes Python dynamic function call


By : Parker
Date : March 29 2020, 07:55 AM
Does that help To invoke the function using it's name as a string, you this can do this
code :
...    
fName = "printHello"
test[fName]()
Related Posts Related Posts :
  • google app engine error ,and i can't open it now.(python)
  • IIS Not Linking to Django with PyISAPIe
  • Create two separate windows in terminal
  • Killing a subprocess including its children from python
  • google search rankings and trends api
  • Easiest way to automatically download required modules in Python?
  • How to read a string one letter at a time in python
  • Python pixel manipulation library
  • python cx_Freeze egg problem
  • How can I select all rows with sqlalchemy?
  • Converting IPv4 or IPv6 address to a long for comparisons
  • Converting BMP to Grey Scale in Image Module Python
  • Python: Memory usage and optimization when modifying lists
  • Mod_wsgi versus fapws3 - Django
  • In Django, how to create tables from an SQL file when syncdb is run
  • What's the pythonic way to use getters and setters?
  • python regular expression for domain names
  • Pickling a class definition
  • How to catch login failures with PySVN?
  • Python: how to enclose strings in a list with < and >
  • Python: finding lowest integer
  • efficiently finding the interval with non-zeros in scipy/numpy in Python?
  • How to convert Selenese (html) to Python programmatically?
  • fade out in Image module Python
  • local variable 'sresult' referenced before assignment
  • how to transfer a python object between two requests?
  • Getting weird python error when I run a simple django script in Eclipse, not happening in console
  • shadow
    Privacy Policy - Terms - Contact Us © 35dp-dentalpractice.co.uk