1
mind3x 2014-08-28 22:17:40 +08:00 1
看RFC,送HEAD请求,再根据各种和最近修改时间有关的header来判断 http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html
|
2
WKPlus 2014-08-28 23:12:18 +08:00 1
"When running Wget with -N, with or without -r or -p, the decision as to whether or not to download a newer copy of a file depends on the local and remote timestamp and size of the file. -nc may not be specified at the same time as -N."
man里面的解释是根据timestamp和size. |