示例：在VxWorks操作系统中学习文件读写操作

dev

1.create file on floopy disk and write contents：
-> pdev=fdDevCreate(0,0,0,0)     /* A:,1.44M,whole disk,offset */
-> dosFsMkfs("/fd0"，pdev)  
-> fd=creat("/fd0/myfile",2)  or   -> fp=fopen("/fd0/myfile","w")
-> buf="what you want to write to file" 
-> write(fd,buf,strlen(buf)+1)  or -> fprintf(fp,buf)
-> close(fd)    or  -> fclose(fp)

2.open file and read contents from floopy disk:
-> readbuf=malloc(100)   
-> fd=open("/fd0/myfile",2)  or -> fp=fopen("/fd0/myfile","r")
-> read(fd,readbuf,100)   or -> fread(readbuf,1,50,fp)
-> printf readbuf   
-> close(fd)    or -> close(fp)
      

3.on simpc shell:
-> fp=fopen("host:d:/temp/myfile","w")
-> fprintf(fp,"kjkkhjk")
-> fclose(fp)