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【转】老外学习C语言套路

Learning C

If you don't know C and plan to use it for osdeving, it might be profitable to begin with some C language exercises. A good start (you still need to find tutorials, these are just exercises):

  • program that writes a string, asks for your name, writes two line breaks and writes another string and the provided name;
  • implement strcopy(), strncopy(), strncmp() and other string manipulation functions. What is a buffer overflow?
  • implement memmove() or memcpy(). Can you do it with inline assembly so it be faster?
  • use inline assembly to perform CPUID and interpret the results;
  • use typedefs to name uint32 for a 32-bit unsigned integer type; what type is signed 16-bit?
  • use structs and pointers to implement a singly linked lists.
  • divide the program with singly linked lists to main.c, list.c and list.h. What is a header guard?
  • learn about inline, static, volatile; ternary operator; casts;
  • use C preprocessor to write MAX, MIN macros; to print out the current function name, line number;
  • use C preprocessor to write a log function which takes a level for the first argument, and uses printf() on the rest of the arguments if the level is higher or equal to current logging threshold.

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