1 Long: header
2 Short: H
3 Arg: <header/@file>
4 Help: Pass custom header(s) to server
5 Protocols: HTTP
6 Category: http
7 See-also: user-agent referer
8 ---
9 Extra header to include in the request when sending HTTP to a server. You may
10 specify any number of extra headers. Note that if you should add a custom
11 header that has the same name as one of the internal ones curl would use, your
12 externally set header will be used instead of the internal one. This allows
13 you to make even trickier stuff than curl would normally do. You should not
14 replace internally set headers without knowing perfectly well what you're
15 doing. Remove an internal header by giving a replacement without content on
16 the right side of the colon, as in: -H \&"Host:". If you send the custom
17 header with no-value then its header must be terminated with a semicolon, such
18 as \-H \&"X-Custom-Header;" to send "X-Custom-Header:".
19 
20 curl will make sure that each header you add/replace is sent with the proper
21 end-of-line marker, you should thus \fBnot\fP add that as a part of the header
22 content: do not add newlines or carriage returns, they will only mess things
23 up for you.
24 
25 This option can take an argument in @filename style, which then adds a header
26 for each line in the input file. Using @- will make curl read the header file
27 from stdin. Added in 7.55.0.
28 
29 You need --proxy-header to send custom headers intended for a HTTP
30 proxy. Added in 7.37.0.
31 
32 Passing on a "Transfer-Encoding: chunked" header when doing a HTTP request
33 with a request body, will make curl send the data using chunked encoding.
34 
35 Example:
36 
37  curl -H "X-First-Name: Joe" http://example.com/
38 
39 \fBWARNING\fP: headers set with this option will be set in all requests - even
40 after redirects are followed, like when told with --location. This can lead to
41 the header being sent to other hosts than the original host, so sensitive
42 headers should be used with caution combined with following redirects.
43 
44 This option can be used multiple times to add/replace/remove multiple headers.
45