gcc
无法自动查找动态链接库,除非我明确指定其路径。首先,我正在使用libmemcached
,它已经通过brew
安装。
17:27:14 shell% ls -la /usr/local/lib/libmemcached*
lrwxr-xr-x 1 user wheel 55 Sep 2 12:42 /usr/local/lib/libmemcached.11.dylib -> ../Cellar/libmemcached/1.0.17/lib/libmemcached.11.dylib
lrwxr-xr-x 1 user wheel 48 Sep 2 12:42 /usr/local/lib/libmemcached.a -> ../Cellar/libmemcached/1.0.17/lib/libmemcached.a
lrwxr-xr-x 1 user wheel 52 Sep 2 12:42 /usr/local/lib/libmemcached.dylib -> ../Cellar/libmemcached/1.0.17/lib/libmemcached.dylib
lrwxr-xr-x 1 user wheel 58 Sep 2 12:42 /usr/local/lib/libmemcachedutil.2.dylib -> ../Cellar/libmemcached/1.0.17/lib/libmemcachedutil.2.dylib
lrwxr-xr-x 1 user wheel 52 Sep 2 12:42 /usr/local/lib/libmemcachedutil.a -> ../Cellar/libmemcached/1.0.17/lib/libmemcachedutil.a
lrwxr-xr-x 1 user wheel 56 Sep 2 12:42 /usr/local/lib/libmemcachedutil.dylib -> ../Cellar/libmemcached/1.0.17/lib/libmemcachedutil.dylib
我的hellomemcached.c
看起来像这样:
#include <libmemcached/memcached.h>
int main ()
{
memcached_return_t rc;
memcached_server_st* servers = NULL;
memcached_st* memcached;
// initialize the memcached structure
memcached = memcached_create(NULL);
if (!memcached)
return 0;
}
使用以下命令进行编译,最终成功完成:
gcc -arch x86_64 /usr/local/lib/libmemcached.dylib -I/usr/local/include -o hellomemcached hellomemcached.c
但是如果我尝试使用包含库的文件夹路径来编译它:
gcc -arch x86_64 -L/usr/local/lib -I/usr/local/include -o hellomemcached hellomemcached.c
我收到一个错误:
Undefined symbols for architecture x86_64:
"_memcached_create", referenced from:
_main in ccYCwHa6.o
ld: symbol(s) not found for architecture x86_64
显然在这种情况下找不到库。我做错了什么?