我正在编写一个程序来监视select()
键盘和鼠标设备文件。它等待这些文件上的任何写入操作(这应该在有击键或鼠标移动时发生),并且一旦有写入操作,就会执行一些作业。
但这不起作用。我的代码如下。
#include<stdio.h>
#include<string.h>
#include<sys/types.h>
#include<sys/stat.h>
#include<fcntl.h>
#include<linux/input.h>
#include<linux/uinput.h>
#include<sys/time.h>
#include<unistd.h>
void main()
{
int mouse_fd,kbd_fd,fd_max;
struct input_event ev;
fd_set rfs,wfs;
if((mouse_fd=open("/dev/input/event3",O_WRONLY))==-1)
{
printf("opening mouse device file has failed \n");
}
else
{
printf("opening mouse device file has been successfull \n");
}
if((kbd_fd=open("/dev/input/event2",O_WRONLY))==-1)
{
printf("opening keyboard device file has failed \n");
}
else
{
printf("opening keyboard device file has been successfull \n");
}
FD_ZERO(&rfs);
FD_ZERO(&wfs);
FD_SET(mouse_fd,&rfs);
FD_SET(kbd_fd,&rfs);
FD_SET(mouse_fd,&wfs);
FD_SET(kbd_fd,&wfs);
if(mouse_fd>kbd_fd)
{
fd_max=mouse_fd;
}
else
{
fd_max=kbd_fd;
}
while(1)
{
select((fd_max+1),&rfs,NULL,NULL,NULL);
sleep(2);
if(FD_ISSET(mouse_fd,&rfs))
{
printf("test mouse \n");
}
if(FD_ISSET(kbd_fd,&rfs))
{
printf("test keyboard \n");
}
}
}
当我执行该程序时,它会产生这样的输出,
[root@localhost Project]# gcc select.c
[root@localhost Project]# ./a.out
opening mouse device file has been successfull
opening keyboard device file has been successfull
test keyboard
test keyboard
test keyboard
test keyboard
test keyboard
test keyboard
test keyboard
test keyboard
test keyboard
即使我没有按任何键。此外,即使存在物理鼠标移动,鼠标设备文件也不会被 select() 选择。
我究竟做错了什么?