令人不解的问题
#include "stdio.h "
#include "string.h "
#include "stdlib.h "
#include "time.h "
#define MAX_PKT 1024
#define MAX_SEQ 7
typedef enum {FALSE, TRUE} boolean;
typedef unsigned int seq_nr;
typedef enum {dat, ack, nak} frame_kind;
typedef enum event_type {timeout, frame_arrival};
typedef struct
{frame_kind kind;
seq_nr seq;
seq_nr ack;
char info[1024];
} frame;
void from_network_layer(frame *fra)
{
printf( "输入信息: ");
memset(fra-> info, 0, strlen(fra-> info));
for(int i = 0; ; i++)
{
fra-> info[i] = getchar();
if ( '\n ' == fra-> info[i])
{
fra-> info[++i] = '\0 ';
break;
}
}
}
void to_physical_layer(frame *fra)
{
FILE *fp1;
char buf[1024];
char temp;
memset(buf, 0 ,strlen(buf));
switch(fra-> kind)
{
case dat:
strcpy(buf, "dat ");
break;
case ack:
strcpy(buf, "ack ");
break;
case nak:
strcpy(buf, "nak ");
break;
}
itoa(fra-> ack, &temp, 10);
strcat(buf, &temp);
itoa(fra-> seq, &temp, 10);
strcat(buf, &temp);
strcat(buf, fra-> info);
//strcat(buf, '/0 ');
if(0 == (fp1= fopen( "d:\\a.txt ", "r ")))
{
printf( "文件创建失败 ");
fclose(fp1);
}
else
{
fwrite(buf, 1, 1024, fp1);
fclose(fp1);
}
printf( "success ");
}
event_type wait_for_event()
{
return frame_arrival;
}
void main()
{
seq_nr ack = 0;
frame send, rev;
event_type event;
from_network_layer(&send);
send.kind = dat;
send.ack = 0;
send.seq = 0;
to_physical_layer(&send);
event = wait_for_event();
}
一调试到WAIT_FOR_EVENT()RETURN就显示UNHANDLED EXCEPTION,如果把TO_PHYSICAL_LAY()屏蔽就能正常返回,高手来指点下,小弟先谢谢了!
[解决办法]
memset(buf, 0 ,sizeof(buf));
[解决办法]
memset没有见过用strlen的，而且还是初始化用strlen，要不就用strcpy()
fp1文件创建失败，肯定不会用到fclose(fp1);
至于itoa(fra-> ack, &temp, 10);因为是静态分配char[16]，所以&temp和temp是一样，指向分配空间的首地址，不改也可以
如果是malloc动态分配，&temp指向存放地址值的变量，就一定要用temp
路过接分^_^
[解决办法]
char temp[16];
.....
itoa(fra-> ack, temp, 10);
路过接分^_^
