我正在编写一个通过select()
键盘和鼠标设备文件进行监视的程序。它等待对这些文件的任何写操作(这应该在有击键或鼠标移动时发生),并且一旦有写操作,就会执行一些作业。
但它不起作用。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,即使有物理鼠标移动,select() 也不会选择鼠标设备文件。
我究竟做错了什么?