请教 Python 如何调用 arm 编译的 so 文件?

[checgg]

so 文件信息

# readelf -h libencrypt.so

ELF Header:
  Magic:   7f 45 4c 46 01 01 01 00 00 00 00 00 00 00 00 00
  Class:                             ELF32
  Data:                              2's complement, little endian
  Version:                           1 (current)
  OS/ABI:                            UNIX - System V
  ABI Version:                       0
  Type:                              DYN (Shared object file)
  Machine:                           ARM
  Version:                           0x1
  Entry point address:               0x0
  Start of program headers:          52 (bytes into file)
  Start of section headers:          16768 (bytes into file)
  Flags:                             0x5000000, Version5 EABI
  Size of this header:               52 (bytes)
  Size of program headers:           32 (bytes)
  Number of program headers:         7
  Size of section headers:           40 (bytes)
  Number of section headers:         21
  Section header string table index: 20

python 及系统版本信息（ docker 容器）

root@arm32v7-openjdk:/MyApp/pytest# python -V
Python 2.7.13
root@arm32v7-openjdk:/MyApp/pytest# uname -a
Linux arm32v7-openjdk 4.9.41-moby #1 SMP Wed Sep 6 00:05:16 UTC 2017 armv7l GNU/Linux

python 代码

import ctypes
ll = ctypes.cdll.LoadLibrary
"""
1 有试过绝对路径和把这个库文件 copy 到 /usr/local/lib/ 目录下
2 文件肯定存在
3 权限是 777
"""
lib = ll("./libencrypt.so")

报错信息

root@arm32v7-openjdk:/MyApp/pytest# python test.py
Traceback (most recent call last):
  File "test.py", line 3, in <module>
    lib = ll("./libencrypt.so")
  File "/usr/lib/python2.7/ctypes/__init__.py", line 440, in LoadLibrary
    return self._dlltype(name)
  File "/usr/lib/python2.7/ctypes/__init__.py", line 362, in __init__
    self._handle = _dlopen(self._name, mode)
OSError: ./libencrypt.so: cannot open shared object file: No such file or directory

[checgg]

顺便一提,用 java 写也是报同样的错
```
public class test {
public static void main(String[] args) {
System.out.print("Hello world");
String so = "./libencrypt.so";
System.load(so);
}
}

```

[Xiaobaixiao]

把 test.py 移动到 libencrypt.so 所在文件夹，或者添加指定执行该命令的文件夹参数试试（如果有）

[checgg]

@Xiaobaixiao 是在同目录.

[virusdefender]

strace python test.py 看看系统调用

[wevsty]

提示不是很清楚么 cannot open shared object file: No such file or directory
找不到 libencrypt.so 这个文件，检查路径，工作目录，或者干脆写绝对路径上去。

[rookiebulls]

路径问题，拿到当前 py 脚本的路径，再 os.path.join 拼一下就可以了

[zsj950618]

ldd libencrypt.so 看下，也有可能是 ld 路径错了。

[izoabr]

ctypes.cdll.LoadLibrary 的 path 问题，你试试放到 python 的 lib 目录里去调用