CURLOPT_PROTOCOLS(3) Library Functions Manual CURLOPT_PROTOCOLS(3)
NAME
CURLOPT_PROTOCOLS - allowed protocols
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROTOCOLS, long bitmask);
DESCRIPTION
This option is deprecated. We strongly recommend using CURLOPT_PROTO-
COLS_STR(3) instead because this option cannot control all available
protocols.
Pass a long that holds a bitmask of protocol bits. If used, this bitmask
limits what protocols libcurl may use in the transfer. This allows you
to have a libcurl built to support a wide range of protocols but still
limit specific transfers to only be allowed to use a subset of them. By
default libcurl accepts all protocols it supports (CURLPROTO_ALL). See
also CURLOPT_REDIR_PROTOCOLS(3).
These are the available protocol defines:
CURLPROTO_DICT
CURLPROTO_FILE
CURLPROTO_FTP
CURLPROTO_FTPS
CURLPROTO_GOPHER
CURLPROTO_HTTP
CURLPROTO_HTTPS
CURLPROTO_IMAP
CURLPROTO_IMAPS
CURLPROTO_LDAP
CURLPROTO_LDAPS
CURLPROTO_POP3
CURLPROTO_POP3S
CURLPROTO_RTMP
CURLPROTO_RTMPE
CURLPROTO_RTMPS
CURLPROTO_RTMPT
CURLPROTO_RTMPTE
CURLPROTO_RTMPTS
CURLPROTO_RTSP
CURLPROTO_SCP
CURLPROTO_SFTP
CURLPROTO_SMB
CURLPROTO_SMBS
CURLPROTO_SMTP
CURLPROTO_SMTPS
CURLPROTO_TELNET
CURLPROTO_TFTP
DEFAULT
All protocols built-in.
PROTOCOLS
This functionality affects all supported protocols
EXAMPLE
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 HTTP, TFTP and SFTP */
curl_easy_setopt(curl, CURLOPT_PROTOCOLS,
(long)CURLPROTO_HTTP | CURLPROTO_TFTP | CURLPROTO_SFTP);
/* Perform the request */
curl_easy_perform(curl);
}
}
DEPRECATED
Deprecated since 7.85.0.
AVAILABILITY
Added in curl 7.19.4
RETURN VALUE
curl_easy_setopt(3) returns a CURLcode indicating success or error.
CURLE_OK (0) means everything was OK, non-zero means an error occurred,
see libcurl-errors(3).
SEE ALSO
CURLOPT_DEFAULT_PROTOCOL(3), CURLOPT_REDIR_PROTOCOLS(3), CURLOPT_URL(3)
libcurl 2026-07-12 CURLOPT_PROTOCOLS(3)
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