python을 C에서 사용하기

C 에서 python을 불러서 사용하는 방법인데, 아직 복잡한 예제는 발견하지 못했다.

테스트한 플랫폼은
Fedora Core 6
Python 2.4.3 이다.

# cat py.c

#include <Python.h> int main() {         Py_Initialize();         PyRun_SimpleString("print 'Hello Python C/API'");         Py_Finalize();         return 0; } [링크 : http://koichitamura.blogspot.com/2008/06/this-is-small-python-capi-tutorial.html]

# gcc py.c -I/usr/include/python2.4 -lpython2.4
# a.out
Hello Python C/API


이렇게 메시지가 출력된다.

아마 2.4와 2.6이 혼합되어 설치되어있고, 2.6이 정상설치가 되지 않은듯 싶다.
옵션에 따라서 이러한 오류가 발생했다.

# gcc py.c -I/usr/local/include/python2.6 -L/usr/local/lib/libpython2.6.a
/tmp/cc88iTD7.o: In function `main':
py.c:(.text+0x12): undefined reference to `Py_Initialize'
py.c:(.text+0x26): undefined reference to `PyRun_SimpleStringFlags'
py.c:(.text+0x2b): undefined reference to `Py_Finalize'
collect2: ld returned 1 exit status

# gcc py.c -I/usr/local/include/python2.6 -lpython2.6
/usr/local/lib/libpython2.6.a(posixmodule.o): In function `posix_tmpnam':
./Modules/posixmodule.c:7180: warning: the use of `tmpnam_r' is dangerous, better use `mkstemp'
/usr/local/lib/libpython2.6.a(posixmodule.o): In function `posix_tempnam':
./Modules/posixmodule.c:7135: warning: the use of `tempnam' is dangerous, better use `mkstemp'
/usr/local/lib/libpython2.6.a(signalmodule.o): In function `timeval_from_double':
./Modules/signalmodule.c:106: undefined reference to `floor'
./Modules/signalmodule.c:107: undefined reference to `fmod'
./Modules/signalmodule.c:106: undefined reference to `floor'
./Modules/signalmodule.c:107: undefined reference to `fmod'
/usr/local/lib/libpython2.6.a(floatobject.o): In function `float_pow':
Objects/floatobject.c:972: undefined reference to `pow'
/usr/local/lib/libpython2.6.a(floatobject.o): In function `float_divmod':
Objects/floatobject.c:856: undefined reference to `fmod'
/usr/local/lib/libpython2.6.a(floatobject.o): In function `float_rem':
Objects/floatobject.c:834: undefined reference to `fmod'
/usr/local/lib/libpython2.6.a(longobject.o): In function `PyLong_FromString':
Objects/longobject.c:1610: undefined reference to `log'
Objects/longobject.c:1610: undefined reference to `log'
/usr/local/lib/libpython2.6.a(dynload_shlib.o): In function `_PyImport_GetDynLoadFunc':
Python/dynload_shlib.c:94: undefined reference to `dlsym'
Python/dynload_shlib.c:130: undefined reference to `dlopen'
Python/dynload_shlib.c:141: undefined reference to `dlsym'
Python/dynload_shlib.c:133: undefined reference to `dlerror'
/usr/local/lib/libpython2.6.a(thread.o): In function `_pythread_pthread_set_stacksize':
Python/thread_pthread.h:519: undefined reference to `pthread_attr_setstacksize'
/usr/local/lib/libpython2.6.a(thread.o): In function `PyThread_release_lock':
Python/thread_pthread.h:374: undefined reference to `sem_post'
/usr/local/lib/libpython2.6.a(thread.o): In function `PyThread_free_lock':
Python/thread_pthread.h:320: undefined reference to `sem_destroy'
/usr/local/lib/libpython2.6.a(thread.o): In function `PyThread_allocate_lock':
Python/thread_pthread.h:296: undefined reference to `sem_init'
/usr/local/lib/libpython2.6.a(thread.o): In function `PyThread_acquire_lock':
Python/thread_pthread.h:351: undefined reference to `sem_trywait'
Python/thread_pthread.h:349: undefined reference to `sem_wait'
/usr/local/lib/libpython2.6.a(thread.o): In function `PyThread_start_new_thread':
Python/thread_pthread.h:171: undefined reference to `pthread_attr_setstacksize'
Python/thread_pthread.h:181: undefined reference to `pthread_create'
Python/thread_pthread.h:197: undefined reference to `pthread_detach'
/usr/local/lib/libpython2.6.a(thread.o): In function `PyThread_release_lock':
Python/thread_pthread.h:374: undefined reference to `sem_post'
Python/thread_pthread.h:374: undefined reference to `sem_post'
Python/thread_pthread.h:374: undefined reference to `sem_post'
/usr/local/lib/libpython2.6.a(thread.o): In function `PyThread_allocate_lock':
Python/thread_pthread.h:296: undefined reference to `sem_init'
Python/thread_pthread.h:296: undefined reference to `sem_init'
/usr/local/lib/libpython2.6.a(posixmodule.o): In function `posix_forkpty':
posixmodule.c:(.text+0x2653): undefined reference to `forkpty'
/usr/local/lib/libpython2.6.a(posixmodule.o): In function `posix_openpty':
posixmodule.c:(.text+0x26fc): undefined reference to `openpty'
/usr/local/lib/libpython2.6.a(complexobject.o): In function `_Py_c_abs':
Objects/complexobject.c:214: undefined reference to `hypot'
/usr/local/lib/libpython2.6.a(complexobject.o): In function `_Py_c_pow':
Objects/complexobject.c:143: undefined reference to `hypot'
Objects/complexobject.c:144: undefined reference to `pow'
Objects/complexobject.c:145: undefined reference to `atan2'
Objects/complexobject.c:151: undefined reference to `cos'
Objects/complexobject.c:152: undefined reference to `sin'
Objects/complexobject.c:148: undefined reference to `exp'
Objects/complexobject.c:149: undefined reference to `log'
collect2: ld returned 1 exit status

웃긴건, 헤더는 2.6으로 링킹은 2.4로 해도 이상이 없다는 점이다.
(뭥미?)