fs.read(fd, buffer, offset, length, position, callback)
Read data
from the file specified by fd
.
buffer
is the buffer that the data will be written to.
offset
is the offset in the buffer to start writing at.
为什么不是这样:
buffer
is the buffer that the data will be read to.
offset
is the offset in the buffer to start reading at.
要把数据从文件里读出来写入buffer,offset也是buffer的偏移量