Linux環境編程之進程(三)：函數間跳轉

標籤：setjmp   longjmp   函數間跳轉   

引言：在編寫程式時，經常在函數內部使用goto語句來跳轉，從而進行出錯處理，那麼如果想要在函數之間進行跳轉該怎麼做呢？使用setjmp和longjmp函數。

給出樣本程式：

#include <stdio.h>#include <stdlib.h>#include <setjmp.h>static void f1(int, int, int, int);static void f2(void);static jmp_buf jmpbuffer;static int globval;intmain(void){int autoval;register int regival;volatile int volaval;static int  statval;globval = 1;autoval = 2;regival = 3; volaval = 4;statval = 5;if(setjmp(jmpbuffer) != 0){printf("after longjmp:\n");printf("global = %d, autoval = %d, regival  = %d, volaval = %d, statval = %d\n", globval, autoval, regival, volaval, statval);exit(0);}/* * Change variable after setjmp, buf before longjmp. */globval = 95;autoval = 96;regival = 97; volaval = 98;statval = 99;f1(autoval, regival, volaval, statval);/*never returns*/exit(0);}static voidf1(int i, int j, int k, int l){printf("in f1():\n");printf("global = %d, autoval = %d, regival  = %d, volaval = %d, statval = %d\n", globval,i, j, k, l);f2();}static voidf2(void){longjmp(jmpbuffer, 1);}

編譯器測試結果：

in f1():global = 95, autoval = 96, regival  = 97, volaval = 98, statval = 99after longjmp:global = 95, autoval = 96, regival  = 97, volaval = 98, statval = 99