curl/docs/libcurl/opts/CURLOPT_FOLLOWLOCATION.3
Jay Satiro e8442e4ffc libcurl: Restrict redirect schemes (follow-up)
- Allow FTPS on redirect.

- Update default allowed redirect protocols in documentation.

Follow-up to 6080ea0.

Ref: https://github.com/curl/curl/pull/4094

Closes https://github.com/curl/curl/pull/4115
2019-07-17 00:48:40 -04:00

82 lines
3.4 KiB
Groff

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.TH CURLOPT_FOLLOWLOCATION 3 "17 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options"
.SH NAME
CURLOPT_FOLLOWLOCATION \- follow HTTP 3xx redirects
.SH SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FOLLOWLOCATION, long enable);
.SH DESCRIPTION
A long parameter set to 1 tells the library to follow any Location: header
that the server sends as part of an HTTP header in a 3xx response. The
Location: header can specify a relative or an absolute URL to follow.
libcurl will issue another request for the new URL and follow new Location:
headers all the way until no more such headers are returned.
\fICURLOPT_MAXREDIRS(3)\fP can be used to limit the number of redirects
libcurl will follow.
libcurl limits what protocols it automatically follows to. The accepted
protocols are set with \fICURLOPT_REDIR_PROTOCOLS(3)\fP. By default libcurl
will allow HTTP, HTTPS, FTP and FTPS on redirect (7.65.2). Older versions of
libcurl allowed all protocols on redirect except those disabled for security
reasons: Since 7.19.4 FILE and SCP are disabled, and since 7.40.0 SMB and SMBS
are also disabled.
When following a Location:, the 3xx response code that redirected it also
dictates which request method it will use in the subsequent request: For 301,
302 and 303 responses libcurl will switch method to GET unless
\fICURLOPT_POSTREDIR(3)\fP instructs libcurl otherwise. All other 3xx codes
will make libcurl send the same method again.
For users who think the existing location following is too naive, too simple
or just lacks features, it is very 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 DEFAULT
0, disabled
.SH PROTOCOLS
HTTP(S)
.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_URL, "http://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 CURLOPT_REDIR_PROTOCOLS "(3), " CURLOPT_PROTOCOLS "(3), "
.BR CURLOPT_POSTREDIR "(3), "
.BR CURLINFO_REDIRECT_URL "(3), " CURLINFO_REDIRECT_COUNT "(3), "