Static library and dynamic library

Linux Under the system Three ways of program operation

Direct operation

g++ main.cpp src/swap.cpp -Iinclude -Wall -std=c++11 -o a.out
./a.out

Link static libraries to generate executables

//  Get into src Under the table of contents 
cd src
//  assembly   Generate swap.o file 
g++ swap.cpp -c -I../include
//  Generate static libraries  libswap.a
ar rs libswap.a swap.o
//  Go back to the parent directory 
cd ..
//  link   Generate executable files  static_main
g++ main.cpp -Iinclude -Lsrc -o static_main
//  Run the executable 
./static_main

Link dynamic library to generate executable file

//  Get into src Under the table of contents 
cd src
//  Generate target file ,fPIC Create an address independent compiler （pic,position independent code）, In order to be able to share among multiple applications .
g++ swap.cpp -I../include -c -fPIC
//  Generate dynamic library  libswap.so
g++ -shared -o libswap.so swap.o
//  The above two steps can be combined into one command  g++ swap.cpp -I../include -fPIC -shared -o libswap.so
//  Go back to the parent directory 
cd ..
//  link   Generate executable files  dynamic_main
g++ main.cpp -Iinclude -Lsrc -lswap -o dynamic_main
//  Run the executable 
LD_LIBRARY_PATH=src ./dynamic_main

Excellent article ： The difference between static library and dynamic library