master-server/deps/curl/docs/libcurl/opts/CURLOPT_FOLLOWLOCATION.3

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.TH CURLOPT_FOLLOWLOCATION 3 "17 Jun 2014" libcurl libcurl
.SH NAME
CURLOPT_FOLLOWLOCATION \- follow HTTP 3xx redirects
.SH SYNOPSIS
.nf
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FOLLOWLOCATION, long enable);
.fi
.SH DESCRIPTION
A long parameter set to 1 tells the library to follow any Location: header
redirects that a HTTP server sends in a 30x response. The Location: header can
specify a relative or an absolute URL to follow.
libcurl issues another request for the new URL and follows subsequent new
Location: redirects all the way until no more such headers are returned or the
maximum limit is reached. \fICURLOPT_MAXREDIRS(3)\fP is used to limit the
number of redirects libcurl follows.
libcurl restricts what protocols it automatically follow redirects to. The
accepted target protocols are set with \fICURLOPT_REDIR_PROTOCOLS(3)\fP. By
default libcurl allows HTTP, HTTPS, FTP and FTPS on redirects.
When following a redirect, the specific 30x response code also dictates which
request method libcurl uses in the subsequent request: For 301, 302 and 303
responses libcurl switches method from POST to GET unless
\fICURLOPT_POSTREDIR(3)\fP instructs libcurl otherwise. All other redirect
response codes make libcurl use the same method again.
For users who think the existing location following is too naive, too simple
or just lacks features, it is easy to instead implement your own redirect
follow logic with the use of \fIcurl_easy_getinfo(3)\fP's
\fICURLINFO_REDIRECT_URL(3)\fP option instead of using
\fICURLOPT_FOLLOWLOCATION(3)\fP.
.SH NOTE
Since libcurl changes method or not based on the specific HTTP response code,
setting \fICURLOPT_CUSTOMREQUEST(3)\fP while following redirects may change
what libcurl would otherwise do and if not that carefully may even make it
misbehave since \fICURLOPT_CUSTOMREQUEST(3)\fP overrides the method libcurl
would otherwise select internally.
.SH DEFAULT
0, disabled
.SH PROTOCOLS
HTTP(S)
.SH EXAMPLE
.nf
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
/* example.com is redirected, so we tell libcurl to follow redirection */
curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
curl_easy_perform(curl);
}
}
.fi
.SH AVAILABILITY
Along with HTTP
.SH RETURN VALUE
Returns CURLE_OK if HTTP is supported, and CURLE_UNKNOWN_OPTION if not.
.SH "SEE ALSO"
.BR CURLINFO_REDIRECT_COUNT (3),
.BR CURLINFO_REDIRECT_URL (3),
.BR CURLOPT_POSTREDIR (3),
.BR CURLOPT_PROTOCOLS (3),
.BR CURLOPT_REDIR_PROTOCOLS (3)