python ctypes 怎么处理函数返回的一般指针
test.c(动态库源代码)
创新互联科技有限公司专业互联网基础服务商,为您提供四川雅安服务器托管,高防服务器,成都IDC机房托管,成都主机托管等互联网服务。
[cpp] view plain copy
// 编译生成动态库: gcc -g -fPIC -shared -o libtest.so test.c
#include stdio.h
#include string.h
#include stdlib.h
typedef struct StructPointerTest
{
char name[20];
int age;
}StructPointerTest, *StructPointer;
StructPointer test() // 返回结构体指针
{
StructPointer p = (StructPointer)malloc(sizeof(StructPointerTest));
strcpy(p-name, "Joe");
p-age = 20;
return p;
}
编译:gcc -g -fPIC -shared -o libtest.so test.c
call.py(python调用C语言生成的动态库):
[python] view plain copy
#!/bin/env python
# coding=UTF-8
from ctypes import *
#python中结构体定义
class StructPointer(Structure):
_fields_ = [("name", c_char * 20), ("age", c_int)]
if __name__ == "__main__":
lib = cdll.LoadLibrary("./libtest.so")
lib.test.restype = POINTER(StructPointer)
p = lib.test()
print "%s: %d" %(p.contents.name, p.contents.age)
最后运行结果:
[plain] view plain copy
[zcm@c_py #112]$make clean
rm -f *.o libtest.so
[zcm@c_py #113]$make
gcc -g -fPIC -shared -o libtest.so test.c
[zcm@c_py #114]$./call.py
Joe: 20
[zcm@c_py #115]$
python使用C函数返回的指针
int* GrabImage();
int GetPixel(int* image, int x, int y);
void SetPixel(int* image, int x, int y, int color);
python 中callback怎么使用
在计算机程序设计中,回调函数,或简称回调(Callback),是指通过函数参数传递到其它代码的,某一块可执行代码的引用。这一设计允许了底层代码调用在高层定义的子程序:
例如:
def my_callback(input):
print "function my_callback was called with %s input" % (input,)
def caller(input, func):
func(input)
for i in range(5):
caller(i, my_callback)
执行结果是:
function my_callback was called with 0 input
function my_callback was called with 1 input
function my_callback was called with 2 input
function my_callback was called with 3 input
function my_callback was called with 4 input
当前名称:python返回函数指针 python指定函数返回值类型
文章转载:http://lswzjz.com/article/dojsejp.html