Python ctypes in_dll string assignment
- by ackdesha
I could use some help assigning to a global C variable in DLL using ctypes.
The following is an example of what I'm trying:
test.c contains the following
#include <stdio.h>
char name[60];
void test(void) {
printf("Name is %s\n", name);
}
On windows (cygwin) I build a DLL (Test.dll) as follows:
gcc -g -c -Wall test.c
gcc -Wall -mrtd -mno-cygwin -shared -W1,--add-stdcall-alias -o Test.dll test.o
When trying to modify the name variable and then calling the C test function using the ctypes interface I get the following...
>>> from ctypes import *
>>> dll = windll.Test
>>> dll
<WinDLL 'Test', handle ... at ...>
>>> f = c_char_p.in_dll(dll, 'name')
>>> f
c_char_p(None)
>>> f.value = 'foo'
>>> f
c_char_p('foo')
>>> dll.test()
Name is Name is 48+?
13
Why does the test function print garbage in this case?
