完善了README.md...

books/fengguojin/src/1-drivermodel/1-7poll/simple/simple.c

@@ -54,26 +54,32 @@ int simple_release(struct inode *inode, struct file *filp)
 
 ssize_t simple_read(struct file *filp, char __user *buf, size_t count,loff_t *f_pos)
 {
-	//printk("wait_event_interruptible before\n");
+	printk("wait_event_interruptible before\n");
 	wait_event_interruptible(read_queue, simple_flag);
-	//printk("wait_event_interruptible after\n");
-	if (copy_to_user( buf, demoBuffer, count))
+	printk("wait_event_interruptible after\n");
+    if (copy_to_user( buf, demoBuffer, count))
 	{
 		count=-EFAULT;
 	}
 
+    printk("read data : %s\n", demoBuffer);
     return count;
 }
 
 ssize_t simple_write(struct file *filp, const char __user *buf, size_t count,loff_t *f_pos)
 {
+	memset(demoBuffer, 0, MAX_SIZE);
 	if (copy_from_user(demoBuffer, buf, count))
 	{
 		count = -EFAULT;
 		goto out;
 	}
-	simple_flag=1;
+
+    printk("write data : %s\n", demoBuffer);
+
+    simple_flag = 1;
     wake_up(&read_queue);
+
 out:
 	return count;
 }
@@ -83,7 +89,7 @@ unsigned int simple_poll(struct file * file, poll_table * pt)
 	unsigned int mask = POLLIN | POLLRDNORM;
 
     printk("poll_wait before\n");
-	poll_wait(file, &read_queue, pt);
+	poll_wait(file, &read_queue, pt);   /*  put current process into the wait queue  */
 	printk("poll_wait after\n");
 
     return mask;

books/fengguojin/src/1-drivermodel/1-7poll/simple/simple.h

@@ -21,10 +21,13 @@
 #define PDEBUGG(fmt, args...) /* nothing: it's a placeholder */
 
 //设备号
-#define simple_MAJOR 224
-#define simple_MINOR 0
-#define COMMAND1 1
-#define COMMAND2 2
+#define     simple_MAJOR    224
+#define     simple_MINOR    0
+#define     COMMAND1        1
+#define     COMMAND2        2
+
+
+#define     MAX_SIZE        256
 
 //设备结构
 struct simple_dev

books/fengguojin/src/1-drivermodel/1-7poll/test/test.c

@@ -3,6 +3,7 @@
 #include <fcntl.h>
 #include <linux/rtc.h>
 #include <linux/ioctl.h>
+#include <sys/select.h>
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -23,9 +24,9 @@ void *readthread(void *arg)
 {
 	char data[MAX_SIZE];
 
-    fd_set      rfds; //¶ÁÃèÊö·û¼¯ºÏ
-    fd_set      wfds; //дÃèÊö·û¼¯ºÏ
-	int         retval = 0;
+    fd_set      rfds;   /*  the set of the readable files   */
+    fd_set      wfds;   /*  the set of the writeable files  */
+    int         retval = 0;
 
     while( 1 )
 	{
@@ -43,8 +44,10 @@ void *readthread(void *arg)
 				exit(-1);
 			}
 			data[retval] = 0;
-			printf("read successfully:%s\n",data);
+			printf("read successfully : %s\n",data);
 		}
+
+        sleep(1);
 	}
     return (void *)0;
 }
@@ -54,8 +57,10 @@ void *readthread(void *arg)
 int main(void)
 {
 
-	int i;
-	int retval;
+	int     i;
+	int     retval;
+    char    str[3][81] = { "gatieme", "wangpanpan", "Hello World!!!" };
+    //char    (*pstr)[81] = str;
 
     fd = open(DEV_FILE, O_RDWR);
     if(fd == -1)
@@ -68,14 +73,18 @@ int main(void)
 	pthread_t   tid;
 	pthread_create(&tid, NULL, readthread, NULL);
 
+    srand(time(NULL));
+
 	while( 1 )
 	{
-		retval = write(fd, "gatieme", strlen("gatieme"));
+        i = rand( ) % 3;
+		retval = write(fd, str[i], strlen(str[i]));
 		if(retval == -1)
 		{
 			perror("write error\n");
 			exit(-1);
 		}
+        sleep(2);
 	}
 
 	close(fd);