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: <time>
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.
docs/cmdline: change to .md for cmdline docs - switch all invidual files documenting command line options into .md, as the documentation is now markdown-looking. - made the parser treat 4-space indents as quotes - switch to building the curl.1 manpage using the "mainpage.idx" file, which lists the files to include to generate it, instead of using the previous page-footer/headers. Also, those files are now also .md ones, using the same format. I gave them underscore prefixes to make them sort separately: _NAME.md, _SYNOPSIS.md, _DESCRIPTION.md, _URL.md, _GLOBBING.md, _VARIABLES.md, _OUTPUT.md, _PROTOCOLS.md, _PROGRESS.md, _VERSION.md, _OPTIONS.md, _FILES.md, _ENVIRONMENT.md, _PROXYPREFIX.md, _EXITCODES.md, _BUGS.md, _AUTHORS.md, _WWW.md, _SEEALSO.md - updated test cases accordingly Closes #12751 2024-01-21 06:18:43 +08:00			`---`
copyright: update all copyright lines and remove year ranges - they are mostly pointless in all major jurisdictions - many big corporations and projects already don't use them - saves us from pointless churn - git keeps history for us - the year range is kept in COPYING checksrc is updated to allow non-year using copyright statements Closes #10205 2023-01-02 20:51:48 +08:00			`c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.`
docs/cmdline-opts: add copyright and license identifier to each file gen.pl now insists on C: and SPDX-License-Identifier: fields to be present in all files. Closes #9002 2022-06-14 06:12:03 +08:00			`SPDX-License-Identifier: curl`
cmdline-docs: more options converted and fixed Now all options are in the new system. 2016-11-28 08:01:13 +08:00			`Long: time-cond`
			`Short: z`
			`Arg: <time>`
			`Help: Transfer based on a time condition`
			`Protocols: HTTP FTP`
docs: add categories to all cmdline opts Adapted gen.pl with 'listcats' This commit is a part of "--help me if you can" Closes #5680 2020-07-13 20:15:04 +08:00			`Category: http ftp`
cmdline-opts: made the 'Added:' field mandatory Since "too old" versions are no longer included in the generated man page, this field is now mandatory so that it won't be forgotten and then not included in the documentation. Closes #7786 2021-09-28 17:50:07 +08:00			`Added: 5.8`
cmdline/docs: add a required 'multi' keyword for each option The keyword specifies how option works when specified multiple times: - single: the last provided value replaces the earlier ones - append: it supports being provided multiple times - boolean: on/off values - mutex: flag-like option that disable anoter flag The 'gen.pl' script then outputs the proper and unified language for each option's multi-use behavior in the generated man page. The multi: header is requires in each .d file and will cause build error if missing or set to an unknown value. Closes #9759 2022-10-18 16:39:43 +08:00			`Multi: single`
docs/cmdline: change to .md for cmdline docs - switch all invidual files documenting command line options into .md, as the documentation is now markdown-looking. - made the parser treat 4-space indents as quotes - switch to building the curl.1 manpage using the "mainpage.idx" file, which lists the files to include to generate it, instead of using the previous page-footer/headers. Also, those files are now also .md ones, using the same format. I gave them underscore prefixes to make them sort separately: _NAME.md, _SYNOPSIS.md, _DESCRIPTION.md, _URL.md, _GLOBBING.md, _VARIABLES.md, _OUTPUT.md, _PROTOCOLS.md, _PROGRESS.md, _VERSION.md, _OPTIONS.md, _FILES.md, _ENVIRONMENT.md, _PROXYPREFIX.md, _EXITCODES.md, _BUGS.md, _AUTHORS.md, _WWW.md, _SEEALSO.md - updated test cases accordingly Closes #12751 2024-01-21 06:18:43 +08:00			`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`
cmdline-docs: more options converted and fixed Now all options are in the new system. 2016-11-28 08:01:13 +08:00			`---`
docs/cmdline: change to .md for cmdline docs - switch all invidual files documenting command line options into .md, as the documentation is now markdown-looking. - made the parser treat 4-space indents as quotes - switch to building the curl.1 manpage using the "mainpage.idx" file, which lists the files to include to generate it, instead of using the previous page-footer/headers. Also, those files are now also .md ones, using the same format. I gave them underscore prefixes to make them sort separately: _NAME.md, _SYNOPSIS.md, _DESCRIPTION.md, _URL.md, _GLOBBING.md, _VARIABLES.md, _OUTPUT.md, _PROTOCOLS.md, _PROGRESS.md, _VERSION.md, _OPTIONS.md, _FILES.md, _ENVIRONMENT.md, _PROXYPREFIX.md, _EXITCODES.md, _BUGS.md, _AUTHORS.md, _WWW.md, _SEEALSO.md - updated test cases accordingly Closes #12751 2024-01-21 06:18:43 +08:00
			# `--time-cond`

cmdline-docs: more options converted and fixed Now all options are in the new system. 2016-11-28 08:01:13 +08:00			`Request a file that has been modified later than the given time and date, or`
cmdline-docs: quote and angle bracket cleanup - make sure angle brackets are escaped - remove a lot of superfluous double quotes - replace several double quotes with backticks To make nicer-looking markdown. Closes #12884 2024-02-07 01:07:07 +08:00			`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.`
cmdline-docs: more options converted and fixed Now all options are in the new system. 2016-11-28 08:01:13 +08:00
			`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.`
time-cond.d: mention what happens on a missing file Closes #11727 2023-08-24 23:36:37 +08:00
			`If provided a non-existing file, curl outputs a warning about that fact and`
			`proceeds to do the transfer without a time condition.`