gpio test sample for edu-riscv64

APP_Framework/Applications/app_test/test_fs.c

@@ -5,27 +5,58 @@
 #define MAX_READ_LENGTH 1000
 
 // sd card here is loaded as "/"
-void TestSD(void)
+void TestFs(void)
 {
     //open the file in sdcard
     int fd = open(SD_FPATH,O_RDWR|O_CREAT);
+    if(fd<0){
+        printf("fs fd open error:%d\n",fd);
+        return;
+    }
+
     char filewords[MAX_READ_LENGTH];
     memset(filewords,0,MAX_READ_LENGTH);
+    const char *input_words = "these words are going to write in fs\n";
 
     //read and write then close file
-    read(fd,filewords,MAX_READ_LENGTH);
+    int err_flag = read(fd,filewords,MAX_READ_LENGTH);
+    if(err_flag<0){
+        printf("read failed,error:%d\n",err_flag);
+        return;
+    }
     printf("read data is \n%s\n",filewords);
-    const char *input_words = "these words are going to write in fs\n";
-    write(fd,input_words,strlen(input_words));
-    close(fd);
+    
+    err_flag = write(fd,input_words,strlen(input_words));
+    if(err_flag<0){
+        printf("write failed,error:%d\n",err_flag);
+        return;
+    }
+    err_flag = close(fd);
+    if(err_flag<0){
+        printf("close failed,error %d\n",err_flag);
+        return ;
+    }
 
     //re-open the file and re-read the file
     fd = open(SD_FPATH,O_RDWR);
-    read(fd,filewords,MAX_READ_LENGTH);
+     if(fd<0){
+        printf("fs fd open error:%d\n",fd);
+        return;
+    }   
+    err_flag = read(fd,filewords,MAX_READ_LENGTH);
+    if(err_flag<0){
+        printf("read failed,error:%d\n",err_flag);
+        return;
+    }    
+
     printf("read data is \n%s\n",filewords);
-    close(fd);
+    err_flag = close(fd);
+    if(err_flag<0){
+        printf("close failed,error:%d\n",err_flag);
+        return;
+    }        
 
     return;
 }
 
-PRIV_SHELL_CMD_FUNCTION(TestSD, a sdcard test sample, PRIV_SHELL_CMD_MAIN_ATTR);
+PRIV_SHELL_CMD_FUNCTION(TestFs, a sd or usb filesystem test sample, PRIV_SHELL_CMD_MAIN_ATTR);