testjmp.c

unix环境高级编程的源代码

#include    <setjmp.h>
#include    "ourhdr.h"

static void    f1(int, int, int);
static void    f2(void);

static jmp_buf    jmpbuffer;

int
main(void)
{
    int                count;
    register int    val;
    volatile int    sum;

    count = 2; val = 3; sum = 4;
    if (setjmp(jmpbuffer) != 0) {
        printf("after longjmp: count = %d, val = %d, sum = %d\n",
                count, val, sum);
        exit(0);
    }
    count = 97; val = 98; sum = 99;
                /* changed after setjmp, before longjmp */
    f1(count, val, sum);        /* never returns */
	exit(0);
}

static void
f1(int i, int j, int k)
{
    printf("in f1(): count = %d, val = %d, sum = %d\n", i, j, k);
    f2();
}

static void
f2(void)
{
    longjmp(jmpbuffer, 1);
}