---
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
SPDX-License-Identifier: curl
Title: CURLOPT_REDIR_PROTOCOLS_STR
Section: 3
Source: libcurl
See-also:
  - CURLINFO_SCHEME (3)
  - CURLOPT_DEFAULT_PROTOCOL (3)
  - CURLOPT_PROTOCOLS (3)
  - CURLOPT_PROTOCOLS_STR (3)
  - CURLOPT_REDIR_PROTOCOLS (3)
Protocol:
  - HTTP
Added-in: 7.85.0
---

# NAME

CURLOPT_REDIR_PROTOCOLS_STR - protocols allowed to redirect to

# SYNOPSIS

~~~c
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_REDIR_PROTOCOLS_STR,
                          char *spec);
~~~

# DESCRIPTION

Pass a pointer to a string that holds a comma-separated list of case
insensitive protocol names (URL schemes). That list limits what protocols
libcurl may use in a transfer that it follows to in a redirect when
CURLOPT_FOLLOWLOCATION(3) is enabled. This option allows applications to
limit specific transfers to only be allowed to use a subset of protocols in
redirections.

Protocols denied by CURLOPT_PROTOCOLS_STR(3) are not overridden by this
option.

By default libcurl allows HTTP, HTTPS, FTP and FTPS on redirects (since
7.65.2).

These are the available protocols:

DICT, FILE, FTP, FTPS, GOPHER, GOPHERS, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS,
MQTT, POP3, POP3S, RTMP, RTMPE, RTMPS, RTMPT, RTMPTE, RTMPTS, RTSP, SCP, SFTP,
SMB, SMBS, SMTP, SMTPS, TELNET, TFTP, WS, WSS

You can set "ALL" as a short-cut to enable all protocols. Note that by setting
all, you may enable protocols that were not supported the day you write this
but are introduced in a future libcurl version.

If trying to set a non-existing protocol or if no matching protocol at all is
set, it returns error.

# DEFAULT

HTTP, HTTPS, FTP and FTPS (Added in 7.65.2).

Older versions defaulted to all protocols except FILE, SCP and since 7.40.0
SMB and SMBS.

# %PROTOCOLS%

# EXAMPLE

~~~c
int main(int argc, char **argv)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    /* pass in the URL from an external source */
    curl_easy_setopt(curl, CURLOPT_URL, argv[1]);

    /* only allow redirects to HTTP and HTTPS URLs */
    curl_easy_setopt(curl, CURLOPT_REDIR_PROTOCOLS_STR, "http,https");

    /* Perform the request */
    curl_easy_perform(curl);
  }
}
~~~

# %AVAILABILITY%

# RETURN VALUE

Returns CURLE_UNKNOWN_OPTION if the option is not implemented,
CURLE_UNSUPPORTED_PROTOCOL if a listed protocol is not supported or disabled,
CURLE_BAD_FUNCTION_ARGUMENT if no protocol is listed else CURLE_OK.
