function library is divided into static library and dynamic library.
0x00. static function library
- it was compiled into target file, so, its not needed at runtime.
- Obviously, when the static library modified, you should recompile the application.
- for example:
Makefile
hello: main.c libhello.a
gcc -o hello main.c -L. -lhello
libhello.a: hello.o
ar cr libhello.a hello.o
hello.o: hello.c
gcc -c hello.c
```
- libhello.a removed or not does not make any difference on the running of "hello"
0x01. dynamic function library
- create dynamic function library
gcc -shared -fPCI -o libhello.so hello.o