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常见（1）. 假定在所有的程序中必须的头文件都已经被正确包含，考虑如下的数据类型： char 为 1 个字节，int 为 4 个字节，long int 为 4 个字节，float 为 4 个字节，double 为个 8 字节，long double 为 8 个字节，指针为 4 个字节 1. Consider the following program: #include
static jmp_buf buf; main() { volatile int b; b =3; if(setjmp(buf)!=0) { printf("%d ", b); exit(0); } b=5; longjmp(buf , 1); } The output for this program is: (a) 3 (b) 5 (c) 0 (d) None of the above The answer is (b) volatile variable isn't affected by the optimization. Its value after the longjump is the last value variable assumed. b last value is 5 hence 5 is printed. setjmp : Sets up for nonlocal goto /* setjmp.h*/ Stores context information such as register values so that the lomgjmp function can return control to the statement following the one calling setjmp.Returns 0 when it is initially cal
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