g++ parameter description

1. -I (capital i)

   Function: Find header files.The search order is -I{path}->/usr/include->usr/local/include

   g++ main.cpp -o main -I /home/linyu/include/

2. -l (lowercase l)

   Role: Specify the library to be linked by the program, followed by the library name.The search order is -I{path}->/usr/lib->usr/local/lib

   Example: The library name of the math library is m, and his library file name is libm.so.Note that the dynamic library is linked first, followed by the static library.

   g++ main.cpp -o main -lzmq

3. -L(uppercase L)

   Libraries placed in /lib, /usr/lib and /usr/local/lib can be linked directly with the -l (lowercase l) parameter, but if the library files are not placed in these three directories, andIf it is placed in another directory, then if we only use the -l parameter, the link will still go wrong. For example, if we put libm.so in the /aaa/bbb/ccc directory, the link parameter is -L /aaa/bbb/ccc -lm

   g++ main.cpp -o main -L /aaa/bbb/ccc -lm

4. -g

   Function: to generate debugging information, the program can be debugged by the debugger.

   g++ -g main.cpp -o main