curl/docs/cmdline-opts/ntlm.md

---
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
SPDX-License-Identifier: curl
Long: ntlm
Help: HTTP NTLM authentication
Mutexed: basic negotiate digest anyauth
Protocols: HTTP
Requires: TLS
Category: auth http
Added: 7.10.6
Multi: mutex
See-also:
  - proxy-ntlm
Example:
  - --ntlm -u user:password $URL
---

# `--ntlm`

Use NTLM authentication. The NTLM authentication method was designed by
Microsoft and is used by IIS web servers. It is a proprietary protocol,
reverse-engineered by clever people and implemented in curl based on their
efforts. This kind of behavior should not be endorsed, you should encourage
everyone who uses NTLM to switch to a public and documented authentication
method instead, such as Digest.

If you want to enable NTLM for your proxy authentication, then use
--proxy-ntlm.
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 01:18:43 +03:00			`---`
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 15:51:48 +03:00			`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 01:12:03 +03:00			`SPDX-License-Identifier: curl`
cmdline-docs: more conversion 2016-11-16 16:20:36 +03:00			`Long: ntlm`
cmdline-opts: shorter help texts In an effort to increase the readability of the "--help all" output on narrow (80 column) terminals. Co-authored-by: Jay Satiro Closes #13169 2024-03-25 12:02:30 +03:00			`Help: HTTP NTLM authentication`
curl.1: Fix cmdline-opts reference errors. --data, --form, and --ntlm were declared to be mutually exclusive with non-existing options. --data and --form referred to --upload (which is short for --upload-file and therefore did work, so this one was merely a bit confusing), --ntlm referred to --negotiated instead of --negotiate. Closes #2612 2018-05-28 15:17:51 +03:00			`Mutexed: basic negotiate digest anyauth`
cmdline-docs: more conversion 2016-11-16 16:20:36 +03:00			`Protocols: HTTP`
			`Requires: TLS`
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 15:15:04 +03:00			`Category: auth http`
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 12:50:07 +03:00			`Added: 7.10.6`
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 11:39:43 +03:00			`Multi: mutex`
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 01:18:43 +03:00			`See-also:`
			`- proxy-ntlm`
			`Example:`
			`- --ntlm -u user:password $URL`
cmdline-docs: more conversion 2016-11-16 16:20:36 +03:00			`---`
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 01:18:43 +03:00
			# `--ntlm`

cmdline-opts: language cleanups Use imperative mood consistently for the first sentence describing an option. "Set this" instead "tell curl to set" or "this sets..." Plus some extra cleanups and rephrasing. Closes #13106 2024-03-12 12:34:58 +03:00			`Use NTLM authentication. The NTLM authentication method was designed by`
cmdline-docs: more conversion 2016-11-16 16:20:36 +03:00			`Microsoft and is used by IIS web servers. It is a proprietary protocol,`
			`reverse-engineered by clever people and implemented in curl based on their`
			`efforts. This kind of behavior should not be endorsed, you should encourage`
			`everyone who uses NTLM to switch to a public and documented authentication`
			`method instead, such as Digest.`

			`If you want to enable NTLM for your proxy authentication, then use`
			`--proxy-ntlm.`