編寫C庫test.c
#include <stdio.h> #include <string.h> int strcmpTest(char *a, char *b) { return strcmp(a, b); } void strcpyTest(char *dst, char *src) { memcpy(dst, src, strlen(dst)); } char *readStr(char *str) { printf("LibPrint: %s addr=%p\n", str, str); return str; }
將c文件生成動態庫:gcc test.c -fPIC -shared -o libtest.so
編寫python文件調用該庫
import ctypes test = ctypes.CDLL("./libtest.so") s1 = '0123456789' s2 = '0123456789' s3 = '987654321' print 'strcmp case:' print test.strcmpTest(s1, s2) print 'strcpy case:' test.strcpyTest(s1, s3) print s1 print 'readStr case:' print test.readStr(s3)
執行結果如下:
strcmp case: 0 strcpy case: 987654321 readStr case: LibPrint: 987654321 addr=0x7fb00c1e0fb4 203296692
我用計算器算了一下,203296692 == 0xc1e0fb4(32bits)。我實驗的機器是64bits,所以看起來addr要大。並且readStr的返回值到python腳本中,是以32bits有符號存儲的。