# 每行打印一個結構體成員 ## 例子 #include <stdio.h> #include <pthread.h> typedef struct { int a; int b; int c; int d; pthread_mutex_t mutex; }ex_st; int main(void) { ex_st st = {1, 2, 3, 4, PTHREAD_MUTEX_INITIALIZER}; printf("%d,%d,%d,%d\n", st.a, st.b, st.c, st.d); return 0; } ## 技巧 默認情況下，gdb以一種“緊湊”的方式打印結構體。以上面代碼為例： (gdb) n 15 printf("%d,%d,%d,%d\n", st.a, st.b, st.c, st.d); (gdb) p st $1 = {a = 1, b = 2, c = 3, d = 4, mutex = {__data = {__lock = 0, __count = 0, __owner = 0, __nusers = 0, __kind = 0, __spins = 0, __list = {__prev = 0x0, __next = 0x0}}, __size = '\000' <repeats 39 times>, __align = 0}} 可以看到結構體的顯示很混亂，尤其是結構體里還嵌套著其它結構體時。 可以執行“set print pretty on”命令，這樣每行只會顯示結構體的一名成員，而且還會根據成員的定義層次進行縮進： (gdb) set print pretty on (gdb) p st $2 = { a = 1, b = 2, c = 3, d = 4, mutex = { __data = { __lock = 0, __count = 0, __owner = 0, __nusers = 0, __kind = 0, __spins = 0, __list = { __prev = 0x0, __next = 0x0 } }, __size = '\000' <repeats 39 times>, __align = 0 } } 詳情參見[gdb手冊](https://sourceware.org/gdb/onlinedocs/gdb/Print-Settings.html#index-print-settings) ## 貢獻者 nanxiao