curl/docs/cmdline-opts/time-cond.md

---

c: Copyright (C) Daniel Stenberg, daniel@haxx.se, et al. SPDX-License-Identifier: curl Long: time-cond Short: z Arg: Help: Transfer based on a time condition Protocols: HTTP FTP Category: http ftp Added: 5.8 Multi: single See-also:

• etag-compare
• remote-time Example:
• -z "Wed 01 Sep 2021 12:18:00" $URL
• -z "-Wed 01 Sep 2021 12:18:00" $URL
• -z file $URL ---

--time-cond

Request a file that has been modified later than the given time and date, or one that has been modified before that time. The date expression can be all sorts of date strings or if it does not match any internal ones, it is treated as a filename and curl tries to get the modification date (mtime) from that file instead. See the curl_getdate(3) man pages for date expression details.

Start the date expression with a dash (-) to make it request for a document that is older than the given date/time, default is a document that is newer than the specified date/time.

If provided a non-existing file, curl outputs a warning about that fact and proceeds to do the transfer without a time condition.