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e3fe020089
Remove the PROTOCOLS section from the source files completely and instead generate them based on the header data in the curldown files. It also generates TLS backend information for options marked for TLS as protocol. Closes #13175
92 lines
2.6 KiB
Markdown
92 lines
2.6 KiB
Markdown
---
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c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
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SPDX-License-Identifier: curl
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Title: CURLOPT_FOLLOWLOCATION
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Section: 3
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Source: libcurl
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See-also:
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- CURLINFO_REDIRECT_COUNT (3)
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- CURLINFO_REDIRECT_URL (3)
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- CURLOPT_POSTREDIR (3)
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- CURLOPT_PROTOCOLS (3)
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- CURLOPT_REDIR_PROTOCOLS (3)
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Protocol:
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- HTTP
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---
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# NAME
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CURLOPT_FOLLOWLOCATION - follow HTTP 3xx redirects
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# SYNOPSIS
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~~~c
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#include <curl/curl.h>
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CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FOLLOWLOCATION, long enable);
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~~~
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# DESCRIPTION
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A long parameter set to 1 tells the library to follow any Location: header
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redirects that an HTTP server sends in a 30x response. The Location: header
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can specify a relative or an absolute URL to follow.
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libcurl issues another request for the new URL and follows subsequent new
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Location: redirects all the way until no more such headers are returned or the
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maximum limit is reached. CURLOPT_MAXREDIRS(3) is used to limit the
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number of redirects libcurl follows.
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libcurl restricts what protocols it automatically follow redirects to. The
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accepted target protocols are set with CURLOPT_REDIR_PROTOCOLS(3). By
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default libcurl allows HTTP, HTTPS, FTP and FTPS on redirects.
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When following a redirect, the specific 30x response code also dictates which
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request method libcurl uses in the subsequent request: For 301, 302 and 303
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responses libcurl switches method from POST to GET unless
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CURLOPT_POSTREDIR(3) instructs libcurl otherwise. All other redirect
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response codes make libcurl use the same method again.
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For users who think the existing location following is too naive, too simple
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or just lacks features, it is easy to instead implement your own redirect
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follow logic with the use of curl_easy_getinfo(3)'s
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CURLINFO_REDIRECT_URL(3) option instead of using
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CURLOPT_FOLLOWLOCATION(3).
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# NOTE
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Since libcurl changes method or not based on the specific HTTP response code,
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setting CURLOPT_CUSTOMREQUEST(3) while following redirects may change
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what libcurl would otherwise do and if not that carefully may even make it
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misbehave since CURLOPT_CUSTOMREQUEST(3) overrides the method libcurl
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would otherwise select internally.
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# DEFAULT
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0, disabled
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# EXAMPLE
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~~~c
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int main(void)
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{
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CURL *curl = curl_easy_init();
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if(curl) {
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curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
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/* example.com is redirected, so we tell libcurl to follow redirection */
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curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
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curl_easy_perform(curl);
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}
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}
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~~~
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# AVAILABILITY
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Along with HTTP
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# RETURN VALUE
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Returns CURLE_OK if HTTP is supported, and CURLE_UNKNOWN_OPTION if not.
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