Tips

• what is REPL?

  • A read–eval–print loop (REPL), also termed an interactive toplevel or language shell, is a simple interactive computer programming environment that takes single user inputs, executes them, and returns the result to the user; a program written in a REPL environment is executed piecewise.

• differences between size_t and ssize_t

  • ssize_t is the same as size_t, but is a signed type - read ssize_t as “signed size_t”. ssize_t is able to represent the number -1, which is returned by several system calls and library functions as a way to indicate error.

• makefile

  • $@ -- 表示目标文件
  • $^ -- 表示所有依赖文件
  • $< -- 表示第一个依赖文件
  • $? -- 表示比目标还要新的依赖文件列表
  • ?= -- 如果没有被赋值过，就赋予等号后面的值

Reference

《Let's Build a Simple Database》