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Expect

"HTTP Expect" , , .

, , "Expect: 100-continue", :

  • 100 , , , ,
  • 417 (Expectation Failed) ; 4xx..

, , Content-Length .

Expect, , cURL, .

Header type Request header
Forbidden request header no

In this article

, 100-continue, 

Expect: 100-continue

100-continue

, (- ) 100 (Continue).

Expect .

PUT /somewhere/fun HTTP/1.1
Host: origin.example.com
Content-Type: video/h264
Content-Length: 1234567890987
Expect: 100-continue

100 (Continue), , 417 (Expectation Failed), - .
RFC 7231, 5.1.1: Expect Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content

  • 417 Expectation Failed
  • 100 Continue

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