下面是从fs.open()返回的文件描述符中提取前fs.read()个字节的示例:
var fs = require('fs');
fs.open('file.txt', 'r', function(status, fd) {
if (status) {
console.log(status.message);
return;
}
var buffer = Buffer.alloc(100);
fs.read(fd, buffer, 0, 100, 0, function(err, num) {
console.log(buffer.toString('utf8', 0, num));
});
});