# Constante predefinite

Constantele de mai jos sunt definite de această extensie și vor fi disponibile doar dacă această extensie a fost compilată în interiorul PHP, sau a fost încărcată dinamic în timpul rulării.

Descriptions and uses for these constants are described within the curl_setopt(), curl_multi_setopt() and curl_getinfo() documentation.

`CURLOPT_AUTOREFERER` (integer)
  Available since PHP 5.1.0
`CURLOPT_COOKIESESSION` (integer)
  Available since PHP 5.1.0
`CURLOPT_DNS_USE_GLOBAL_CACHE` (integer)
`CURLOPT_DNS_CACHE_TIMEOUT` (integer)
`CURLOPT_FTP_SSL` (integer)
  Available since PHP 5.2.0
`CURLFTP_CREATE_DIR` (integer)
  Available since PHP 7.0.7 and cURL 7.19.3
`CURLFTP_CREATE_DIR_NONE` (integer)
  Available since PHP 7.0.7 and cURL 7.19.3
`CURLFTP_CREATE_DIR_RETRY` (integer)
  Available since PHP 7.0.7 and cURL 7.19.3
`CURLFTPSSL_TRY` (integer)
  Available since PHP 5.2.0
`CURLFTPSSL_ALL` (integer)
  Available since PHP 5.2.0
`CURLFTPSSL_CONTROL` (integer)
  Available since PHP 5.2.0
`CURLFTPSSL_NONE` (integer)
  Available since PHP 5.2.0
`CURLOPT_PRIVATE` (integer)
  Available since PHP 5.2.4
`CURLOPT_FTPSSLAUTH` (integer)
  Available since PHP 5.1.0
`CURLOPT_PORT` (integer)
`CURLOPT_FILE` (integer)
`CURLOPT_INFILE` (integer)
`CURLOPT_INFILESIZE` (integer)
`CURLOPT_URL` (integer)
`CURLOPT_PROXY` (integer)
`CURLOPT_VERBOSE` (integer)
`CURLOPT_HEADER` (integer)
`CURLOPT_HTTPHEADER` (integer)
`CURLOPT_NOPROGRESS` (integer)
`CURLOPT_NOBODY` (integer)
`CURLOPT_FAILONERROR` (integer)
`CURLOPT_UPLOAD` (integer)
`CURLOPT_POST` (integer)
`CURLOPT_FTPLISTONLY` (integer)
`CURLOPT_FTPAPPEND` (integer)
`CURLOPT_FTP_CREATE_MISSING_DIRS` (integer)
`CURLOPT_NETRC` (integer)
`CURLOPT_FOLLOWLOCATION` (integer)
  This constant is not available when open_basedir or safe_mode are enabled.
`CURLOPT_FTPASCII` (integer)
`CURLOPT_PUT` (integer)
`CURLOPT_MUTE` (integer)
`CURLOPT_USERPWD` (integer)
`CURLOPT_PROXYUSERPWD` (integer)
`CURLOPT_RANGE` (integer)
`CURLOPT_TIMEOUT` (integer)
`CURLOPT_TIMEOUT_MS` (integer)
`CURLOPT_TCP_NODELAY` (integer)
  Available since PHP 5.2.1
`CURLOPT_POSTFIELDS` (integer)
`CURLOPT_PROGRESSFUNCTION` (integer)
  Available since PHP 5.3.0
`CURLOPT_REFERER` (integer)
`CURLOPT_USERAGENT` (integer)
`CURLOPT_FTPPORT` (integer)
`CURLOPT_FTP_USE_EPSV` (integer)
`CURLOPT_LOW_SPEED_LIMIT` (integer)
`CURLOPT_LOW_SPEED_TIME` (integer)
`CURLOPT_RESUME_FROM` (integer)
`CURLOPT_COOKIE` (integer)
`CURLOPT_SSLCERT` (integer)
`CURLOPT_SSLCERTPASSWD` (integer)
`CURLOPT_WRITEHEADER` (integer)
`CURLOPT_SSL_VERIFYHOST` (integer)
`CURLOPT_COOKIEFILE` (integer)
`CURLOPT_SSLVERSION` (integer)
`CURL_SSLVERSION_DEFAULT` (integer)
`CURL_SSLVERSION_TLSv1` (integer)
`CURL_SSLVERSION_SSLv2` (integer)
`CURL_SSLVERSION_SSLv3` (integer)
`CURL_SSLVERSION_TLSv1_0` (integer)
  Available since PHP 5.5.19 and 5.6.3
`CURL_SSLVERSION_TLSv1_1` (integer)
  Available since PHP 5.5.19 and 5.6.3
`CURL_SSLVERSION_TLSv1_2` (integer)
  Available since PHP 5.5.19 and 5.6.3
`CURLOPT_TIMECONDITION` (integer)
`CURLOPT_TIMEVALUE` (integer)
`CURLOPT_CUSTOMREQUEST` (integer)
`CURLOPT_STDERR` (integer)
`CURLOPT_TRANSFERTEXT` (integer)
`CURLOPT_RETURNTRANSFER` (integer)
`CURLOPT_QUOTE` (integer)
`CURLOPT_POSTQUOTE` (integer)
`CURLOPT_INTERFACE` (integer)
`CURLOPT_KRB4LEVEL` (integer)
`CURLOPT_HTTPPROXYTUNNEL` (integer)
`CURLOPT_FILETIME` (integer)
`CURLOPT_WRITEFUNCTION` (integer)
`CURLOPT_READFUNCTION` (integer)
`CURLOPT_PASSWDFUNCTION` (integer)
`CURLOPT_HEADERFUNCTION` (integer)
`CURLOPT_MAXREDIRS` (integer)
`CURLOPT_MAXCONNECTS` (integer)
`CURLOPT_CLOSEPOLICY` (integer)
  Removed in PHP 5.6.0.
`CURLOPT_FRESH_CONNECT` (integer)
`CURLOPT_FORBID_REUSE` (integer)
`CURLOPT_RANDOM_FILE` (integer)
`CURLOPT_EGDSOCKET` (integer)
`CURLOPT_CONNECTTIMEOUT` (integer)
`CURLOPT_CONNECTTIMEOUT_MS` (integer)
`CURLOPT_SSL_VERIFYPEER` (integer)
`CURLOPT_CAINFO` (integer)
`CURLOPT_CAPATH` (integer)
`CURLOPT_COOKIEJAR` (integer)
`CURLOPT_SSL_CIPHER_LIST` (integer)
`CURLOPT_BINARYTRANSFER` (integer)
`CURLOPT_NOSIGNAL` (integer)
`CURLOPT_PROXYTYPE` (integer)
  Available as of cURL 7.10.
`CURLOPT_BUFFERSIZE` (integer)
`CURLOPT_HTTPGET` (integer)
`CURLOPT_HTTP_VERSION` (integer)
`CURLOPT_SSLKEY` (integer)
`CURLOPT_SSLKEYTYPE` (integer)
`CURLOPT_SSLKEYPASSWD` (integer)
`CURLOPT_SSLENGINE` (integer)
`CURLOPT_SSLENGINE_DEFAULT` (integer)
`CURLOPT_SSLCERTTYPE` (integer)
`CURLOPT_CRLF` (integer)
`CURLOPT_ENCODING` (integer)
`CURLOPT_PROXYPORT` (integer)
`CURLOPT_UNRESTRICTED_AUTH` (integer)
`CURLOPT_FTP_USE_EPRT` (integer)
`CURLOPT_HTTP200ALIASES` (integer)
`CURLOPT_HTTPAUTH` (integer)
`CURLAUTH_BASIC` (integer)
`CURLAUTH_DIGEST` (integer)
`CURLAUTH_GSSNEGOTIATE` (integer)
`CURLAUTH_NEGOTIATE` (integer)
  Available since PHP 7.0.7 and cURL 7.38.0.
`CURLAUTH_NTLM` (integer)
`CURLAUTH_NTLM_WB` (integer)
  Available since PHP 7.0.7 and cURL 7.22.0
`CURLAUTH_ANY` (integer)
`CURLAUTH_ANYSAFE` (integer)
`CURLOPT_PROXYAUTH` (integer)
`CURLOPT_MAX_RECV_SPEED_LARGE` (integer)
  Available since PHP 5.4.0 and cURL 7.15.5
`CURLOPT_MAX_SEND_SPEED_LARGE` (integer)
  Available since PHP 5.4.0 and cURL 7.15.5
`CURLOPT_HEADEROPT` (integer)
  Available since PHP 7.0.7 and cURL 7.37.0
`CURLOPT_PROXYHEADER` (integer)
  Available since PHP 7.0.7 and cURL 7.37.0
`CURLCLOSEPOLICY_LEAST_RECENTLY_USED` (integer)
  Removed in PHP 5.6.0.
`CURLCLOSEPOLICY_LEAST_TRAFFIC` (integer)
  Removed in PHP 5.6.0.
`CURLCLOSEPOLICY_SLOWEST` (integer)
  Removed in PHP 5.6.0.
`CURLCLOSEPOLICY_CALLBACK` (integer)
  Removed in PHP 5.6.0.
`CURLCLOSEPOLICY_OLDEST` (integer)
  Removed in PHP 5.6.0.
`CURLINFO_PRIVATE` (integer)
  Available since PHP 5.2.4
`CURLINFO_EFFECTIVE_URL` (integer)
`CURLINFO_HTTP_CODE` (integer)
  As of PHP 5.5.0 and cURL 7.10.8, this is a legacy alias of `CURLINFO_RESPONSE_CODE`
`CURLINFO_RESPONSE_CODE` (integer)
  Available since PHP 5.5.0 and cURL 7.10.8
`CURLINFO_HEADER_OUT` (integer)
  Available since PHP 5.1.3
`CURLINFO_HEADER_SIZE` (integer)
`CURLINFO_REQUEST_SIZE` (integer)
`CURLINFO_TOTAL_TIME` (integer)
`CURLINFO_NAMELOOKUP_TIME` (integer)
`CURLINFO_CONNECT_TIME` (integer)
`CURLINFO_PRETRANSFER_TIME` (integer)
`CURLINFO_SIZE_UPLOAD` (integer)
`CURLINFO_SIZE_DOWNLOAD` (integer)
`CURLINFO_SPEED_DOWNLOAD` (integer)
`CURLINFO_SPEED_UPLOAD` (integer)
`CURLINFO_FILETIME` (integer)
`CURLINFO_SSL_VERIFYRESULT` (integer)
`CURLINFO_CONTENT_LENGTH_DOWNLOAD` (integer)
`CURLINFO_CONTENT_LENGTH_UPLOAD` (integer)
`CURLINFO_STARTTRANSFER_TIME` (integer)
`CURLINFO_CONTENT_TYPE` (integer)
`CURLINFO_REDIRECT_TIME` (integer)
`CURLINFO_REDIRECT_COUNT` (integer)
`CURLINFO_REDIRECT_URL` (string)
  Available since PHP 5.3.7
`CURLINFO_PRIMARY_IP` (string)
  Available since PHP 5.4.7
`CURLINFO_PRIMARY_PORT` (integer)
  Available since PHP 5.4.7
`CURLINFO_LOCAL_IP` (string)
  Available since PHP 5.4.7
`CURLINFO_LOCAL_PORT` (integer)
  Available since PHP 5.4.7
`CURL_PUSH_OK` (integer)
  Available since PHP 7.1.0 and cURL 7.44.0
`CURL_PUSH_DENY` (integer)
  Available since PHP 7.1.0 and cURL 7.44.0
`CURL_REDIR_POST_301` (integer)
  Available since PHP 7.0.7 and cURL 7.18.2
`CURL_REDIR_POST_302` (integer)
  Available since PHP 7.0.7 and cURL 7.18.2
`CURL_REDIR_POST_303` (integer)
  Available since PHP 7.0.7 and cURL 7.25.1
`CURL_REDIR_POST_ALL` (integer)
  Available since PHP 7.0.7 and cURL 7.18.2
`CURL_TIMECOND_IFMODSINCE` (integer)
`CURL_TIMECOND_IFUNMODSINCE` (integer)
`CURL_TIMECOND_LASTMOD` (integer)
`CURL_VERSION_IPV6` (integer)
`CURL_VERSION_KERBEROS4` (integer)
`CURL_VERSION_KERBEROS5` (integer)
  Available since PHP 7.0.7 and cURL 7.40.0
`CURL_VERSION_HTTP2` (integer)
  Available since PHP 5.5.24 and 5.6.8 and cURL 7.33.0
`CURL_VERSION_PSL` (integer)
  Available since PHP 7.0.7 and cURL 7.47.0
`CURL_VERSION_SSL` (integer)
`CURL_VERSION_UNIX_SOCKETS` (integer)
  Available since PHP 7.0.7 and cURL 7.40.0
`CURL_VERSION_LIBZ` (integer)
`CURLVERSION_NOW` (integer)
`CURLE_OK` (integer)
`CURLE_UNSUPPORTED_PROTOCOL` (integer)
`CURLE_FAILED_INIT` (integer)
`CURLE_URL_MALFORMAT` (integer)
`CURLE_URL_MALFORMAT_USER` (integer)
`CURLE_COULDNT_RESOLVE_PROXY` (integer)
`CURLE_COULDNT_RESOLVE_HOST` (integer)
`CURLE_COULDNT_CONNECT` (integer)
`CURLE_FTP_WEIRD_SERVER_REPLY` (integer)
`CURLE_FTP_ACCESS_DENIED` (integer)
`CURLE_FTP_USER_PASSWORD_INCORRECT` (integer)
`CURLE_FTP_WEIRD_PASS_REPLY` (integer)
`CURLE_FTP_WEIRD_USER_REPLY` (integer)
`CURLE_FTP_WEIRD_PASV_REPLY` (integer)
`CURLE_FTP_WEIRD_227_FORMAT` (integer)
`CURLE_FTP_CANT_GET_HOST` (integer)
`CURLE_FTP_CANT_RECONNECT` (integer)
`CURLE_FTP_COULDNT_SET_BINARY` (integer)
`CURLE_PARTIAL_FILE` (integer)
`CURLE_FTP_COULDNT_RETR_FILE` (integer)
`CURLE_FTP_WRITE_ERROR` (integer)
`CURLE_FTP_QUOTE_ERROR` (integer)
`CURLE_HTTP_NOT_FOUND` (integer)
`CURLE_WRITE_ERROR` (integer)
`CURLE_MALFORMAT_USER` (integer)
`CURLE_FTP_COULDNT_STOR_FILE` (integer)
`CURLE_READ_ERROR` (integer)
`CURLE_OUT_OF_MEMORY` (integer)
`CURLE_OPERATION_TIMEOUTED` (integer)
`CURLE_FTP_COULDNT_SET_ASCII` (integer)
`CURLE_FTP_PORT_FAILED` (integer)
`CURLE_FTP_COULDNT_USE_REST` (integer)
`CURLE_FTP_COULDNT_GET_SIZE` (integer)
`CURLE_HTTP_RANGE_ERROR` (integer)
`CURLE_HTTP_POST_ERROR` (integer)
`CURLE_SSL_CONNECT_ERROR` (integer)
`CURLE_FTP_BAD_DOWNLOAD_RESUME` (integer)
`CURLE_FILE_COULDNT_READ_FILE` (integer)
`CURLE_LDAP_CANNOT_BIND` (integer)
`CURLE_LDAP_SEARCH_FAILED` (integer)
`CURLE_LIBRARY_NOT_FOUND` (integer)
`CURLE_FUNCTION_NOT_FOUND` (integer)
`CURLE_ABORTED_BY_CALLBACK` (integer)
`CURLE_BAD_FUNCTION_ARGUMENT` (integer)
`CURLE_BAD_CALLING_ORDER` (integer)
`CURLE_HTTP_PORT_FAILED` (integer)
`CURLE_BAD_PASSWORD_ENTERED` (integer)
`CURLE_TOO_MANY_REDIRECTS` (integer)
`CURLE_UNKNOWN_TELNET_OPTION` (integer)
`CURLE_TELNET_OPTION_SYNTAX` (integer)
`CURLE_OBSOLETE` (integer)
`CURLE_SSL_PEER_CERTIFICATE` (integer)
`CURLE_GOT_NOTHING` (integer)
`CURLE_SSL_ENGINE_NOTFOUND` (integer)
`CURLE_SSL_ENGINE_SETFAILED` (integer)
`CURLE_SEND_ERROR` (integer)
`CURLE_RECV_ERROR` (integer)
`CURLE_SHARE_IN_USE` (integer)
`CURLE_SSL_CERTPROBLEM` (integer)
`CURLE_SSL_CIPHER` (integer)
`CURLE_SSL_CACERT` (integer)
`CURLE_BAD_CONTENT_ENCODING` (integer)
`CURLE_LDAP_INVALID_URL` (integer)
`CURLE_FILESIZE_EXCEEDED` (integer)
`CURLE_FTP_SSL_FAILED` (integer)
`CURLE_SSH` (integer)
  Available since PHP 5.3.0 and cURL 7.16.1.
`CURLFTPAUTH_DEFAULT` (integer)
  Available since PHP 5.1.0
`CURLFTPAUTH_SSL` (integer)
  Available since PHP 5.1.0
`CURLFTPAUTH_TLS` (integer)
  Available since PHP 5.1.0
`CURLPROXY_HTTP` (integer)
  Available since cURL 7.10.
`CURLPROXY_HTTP_1_0` (integer)
  Available since PHP 7.0.7 and cURL 7.19.3
`CURLPROXY_SOCKS4` (integer)
  Available since PHP 5.2.10 and cURL 7.10.
`CURLPROXY_SOCKS5` (integer)
  Available since cURL 7.10.
`CURL_NETRC_OPTIONAL` (integer)
`CURL_NETRC_IGNORED` (integer)
`CURL_NETRC_REQUIRED` (integer)
`CURL_HTTP_VERSION_NONE` (integer)
`CURL_HTTP_VERSION_1_0` (integer)
`CURL_HTTP_VERSION_1_1` (integer)
`CURL_HTTP_VERSION_2` (integer)
  Available since PHP 7.0.7 and cURL 7.43.0
`CURL_HTTP_VERSION_2TLS` (integer)
  Available since PHP 7.0.7 and cURL 7.47.0
`CURL_HTTP_VERSION_2_PRIOR_KNOWLEDGE` (integer)
  Available since PHP 7.0.7 and cURL 7.49.0
`CURLM_CALL_MULTI_PERFORM` (integer)
`CURLM_OK` (integer)
`CURLM_BAD_HANDLE` (integer)
`CURLM_BAD_EASY_HANDLE` (integer)
`CURLM_OUT_OF_MEMORY` (integer)
`CURLM_INTERNAL_ERROR` (integer)
`CURLMSG_DONE` (integer)
`CURLOPT_KEYPASSWD` (integer)
`CURLOPT_SSH_AUTH_TYPES` (integer)
`CURLOPT_SSH_HOST_PUBLIC_KEY_MD5` (integer)
`CURLOPT_SSH_PRIVATE_KEYFILE` (integer)
`CURLOPT_SSH_PUBLIC_KEYFILE` (integer)
`CURLOPT_SSL_OPTIONS` (integer)
  Available since PHP 5.5.0 and cURL 7.25.0
`CURLSSLOPT_ALLOW_BEAST` (integer)
  Available since PHP 5.5.0 and cURL 7.25.0
`CURLSSLOPT_NO_REVOKE` (integer)
  Available since PHP 7.0.7 and cURL 7.44.0
`CURLOPT_USERNAME` (integer)
  Available since PHP 5.5.0 and cURL 7.19.1
`CURLOPT_SASL_IR` (integer)
  Available since PHP 7.0.7 and cURL 7.31.0
`CURLOPT_DNS_INTERFACE` (integer)
  Available since PHP 7.0.7 and cURL 7.33.0
`CURLOPT_DNS_LOCAL_IP4` (integer)
  Available since PHP 7.0.7 and cURL 7.33.0
`CURLOPT_DNS_LOCAL_IP6` (integer)
  Available since PHP 7.0.7 and cURL 7.33.0
`CURLOPT_XOAUTH2_BEARER` (integer)
  Available since PHP 7.0.7 and cURL 7.33.0
`CURLOPT_LOGIN_OPTIONS` (integer)
  Available since PHP 7.0.7 and cURL 7.34.0
`CURLOPT_EXPECT_100_TIMEOUT_MS` (integer)
  Available since PHP 7.0.7 and cURL 7.36.0
`CURLOPT_SSL_ENABLE_ALPN` (integer)
  Available since PHP 7.0.7 and cURL 7.36.0
`CURLOPT_SSL_ENABLE_NPN` (integer)
  Available since PHP 7.0.7 and cURL 7.36.0
`CURLOPT_PINNEDPUBLICKEY` (integer)
  Available since PHP 7.0.7 and cURL 7.39.0
`CURLOPT_UNIX_SOCKET_PATH` (integer)
  Available since PHP 7.0.7 and cURL 7.40.0
`CURLOPT_SSL_VERIFYSTATUS` (integer)
  Available since PHP 7.0.7 and cURL 7.41.0
`CURLOPT_PATH_AS_IS` (integer)
  Available since PHP 7.0.7 and cURL 7.42.0
`CURLOPT_SSL_FALSESTART` (integer)
  Available since PHP 7.0.7 and cURL 7.42.0
`CURLOPT_PIPEWAIT` (integer)
  Available since PHP 7.0.7 and cURL 7.43.0
`CURLOPT_PROXY_SERVICE_NAME` (integer)
  Available since PHP 7.0.7 and cURL 7.43.0
`CURLOPT_SERVICE_NAME` (integer)
  Available since PHP 7.0.7 and cURL 7.43.0
`CURLOPT_DEFAULT_PROTOCOL` (integer)
  Available since PHP 7.0.7 and cURL 7.45.0
`CURLOPT_STREAM_WEIGHT` (integer)
  Available since PHP 7.0.7 and cURL 7.46.0
`CURLOPT_TFTP_NO_OPTIONS` (integer)
  Available since PHP 7.0.7 and cURL 7.48.0
`CURLOPT_CONNECT_TO` (integer)
  Available since PHP 7.0.7 and cURL 7.49.0
`CURLOPT_TCP_FASTOPEN` (integer)
  Available since PHP 7.0.7 and cURL 7.49.0
`CURLMOPT_PIPELINING` (integer)
  Available since PHP 5.5.0 and cURL 7.16.0.
`CURLMOPT_MAXCONNECTS` (integer)
  Available since PHP 5.5.0 and cURL 7.16.3.
`CURLMOPT_CHUNK_LENGTH_PENALTY_SIZE` (integer)
  Available since PHP 7.0.7 and cURL 7.30.0
`CURLMOPT_CONTENT_LENGTH_PENALTY_SIZE` (integer)
  Available since PHP 7.0.7 and cURL 7.30.0
`CURLMOPT_MAX_HOST_CONNECTIONS` (integer)
  Available since PHP 7.0.7 and cURL 7.30.0
`CURLMOPT_MAX_PIPELINE_LENGTH` (integer)
  Available since PHP 7.0.7 and cURL 7.30.0
`CURLMOPT_MAX_TOTAL_CONNECTIONS` (integer)
  Available since PHP 7.0.7 and cURL 7.30.0
`CURLMOPT_PUSHFUNCTION` (integer)
  Available since PHP 7.1.0 and cURL 7.44.0
`CURLSSH_AUTH_AGENT` (integer)
  Available since PHP 7.0.7 and cURL 7.28.0
`CURLSSH_AUTH_ANY` (integer)
`CURLSSH_AUTH_DEFAULT` (integer)
`CURLSSH_AUTH_HOST` (integer)
`CURLSSH_AUTH_KEYBOARD` (integer)
`CURLSSH_AUTH_NONE` (integer)
`CURLSSH_AUTH_PASSWORD` (integer)
`CURLSSH_AUTH_PUBLICKEY` (integer)
`CURL_WRAPPERS_ENABLED` (integer)
  Defined if PHP was configured with --with-curlwrappers . Moved to PECL in PHP 5.5.0.
`CURLPAUSE_ALL` (integer)
  Available since PHP 5.5.0 and cURL 7.18.0.
`CURLPAUSE_CONT` (integer)
  Available since PHP 5.5.0 and cURL 7.18.0.
`CURLPAUSE_RECV` (integer)
  Available since PHP 5.5.0 and cURL 7.18.0.
`CURLPAUSE_RECV_CONT` (integer)
  Available since PHP 5.5.0 and cURL 7.18.0.
`CURLPAUSE_SEND` (integer)
  Available since PHP 5.5.0 and cURL 7.18.0.
`CURLPAUSE_SEND_CONT` (integer)
  Available since PHP 5.5.0 and cURL 7.18.0.
`CURLPIPE_NOTHING` (integer)
  Available since PHP 7.0.0 and cURL 7.43.0.
`CURLPIPE_HTTP1` (integer)
  Available since PHP 7.0.0 and cURL 7.43.0.
`CURLPIPE_MULTIPLEX` (integer)
  Available since PHP 7.0.0 and cURL 7.43.0.
`CURLPROXY_SOCKS4A` (integer)
  Available since PHP 5.5.23 and PHP 5.6.7 and cURL 7.18.0.
`CURLPROXY_SOCKS5_HOSTNAME` (integer)
  Available since PHP 5.5.23 and PHP 5.6.7 and cURL 7.18.0.
`CURLHEADER_SEPARATE` (integer)
  Available since PHP 7.0.7 and cURL 7.37.0.
`CURLHEADER_UNIFIED` (integer)
  Available since PHP 7.0.7 and cURL 7.37.0.
`CURLPROTO_SMB` (integer)
  Available since PHP 7.0.7 and cURL 7.40.0.
`CURLPROTO_SMBS` (integer)
  Available since PHP 7.0.7 and cURL 7.40.0.
`CURLOPT_REQUEST_TARGET` (integer)
  Available since PHP 7.3.0 and cURL 7.55.0.
`CURLAUTH_GSSAPI` (integer)
  Available since PHP 7.3.0 and cURL 7.54.1
`CURLE_WEIRD_SERVER_REPLY` (integer)
  Available since PHP 7.3.0 and cURL 7.51.0
`CURLINFO_CONTENT_LENGTH_DOWNLOAD_T` (integer)
  Available since PHP 7.3.0 and cURL 7.55.0
`CURLINFO_CONTENT_LENGTH_UPLOAD_T` (integer)
  Available since PHP 7.3.0 and cURL 7.55.0
`CURLINFO_HTTP_VERSION` (integer)
  Available since PHP 7.3.0 and cURL 7.50.0
`CURLINFO_PROTOCOL` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLINFO_PROXY_SSL_VERIFYRESULT` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLINFO_SCHEME` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLINFO_SIZE_DOWNLOAD_T` (integer)
  Available since PHP 7.3.0 and cURL 7.50.0
`CURLINFO_SIZE_UPLOAD_T` (integer)
  Available since PHP 7.3.0 and cURL 7.50.0
`CURLINFO_SPEED_DOWNLOAD_T` (integer)
  Available since PHP 7.3.0 and cURL 7.50.0
`CURLINFO_SPEED_UPLOAD_T` (integer)
  Available since PHP 7.3.0 and cURL 7.50.0
`CURL_MAX_READ_SIZE` (integer)
  Available since PHP 7.3.0 and cURL 7.53.0
`CURLOPT_ABSTRACT_UNIX_SOCKET` (integer)
  Available since PHP 7.3.0 and cURL 7.53.0
`CURLOPT_KEEP_SENDING_ON_ERROR` (integer)
  Available since PHP 7.3.0 and cURL 7.51.0
`CURLOPT_PRE_PROXY` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_CAINFO` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_CAPATH` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_CRLFILE` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_KEYPASSWD` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_PINNEDPUBLICKEY` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_SSLCERT` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_SSLCERTTYPE` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_SSL_CIPHER_LIST` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_SSLKEY` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_SSLKEYTYPE` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_SSL_OPTIONS` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_SSL_VERIFYHOST` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_SSL_VERIFYPEER` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_SSLVERSION` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_TLSAUTH_PASSWORD` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_TLSAUTH_TYPE` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_PROXY_TLSAUTH_USERNAME` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURLOPT_SOCKS5_AUTH` (integer)
  Available since PHP 7.3.0 and cURL 7.55.0
`CURLOPT_SUPPRESS_CONNECT_HEADERS` (integer)
  Available since PHP 7.3.0 and cURL 7.54.0
`CURLPROXY_HTTPS` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURL_SSLVERSION_MAX_DEFAULT` (integer)
  Available since PHP 7.3.0 and cURL 7.54.0
`CURL_SSLVERSION_MAX_NONE` (integer)
  Available since PHP 7.3.0 and cURL 7.54.0
`CURL_SSLVERSION_MAX_TLSv1_0` (integer)
  Available since PHP 7.3.0 and cURL 7.54.0
`CURL_SSLVERSION_MAX_TLSv1_1` (integer)
  Available since PHP 7.3.0 and cURL 7.54.0
`CURL_SSLVERSION_MAX_TLSv1_2` (integer)
  Available since PHP 7.3.0 and cURL 7.54.0
`CURL_SSLVERSION_MAX_TLSv1_3` (integer)
  Available since PHP 7.3.0 and cURL 7.54.0
`CURL_SSLVERSION_TLSv1_3` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0
`CURL_VERSION_HTTPS_PROXY` (integer)
  Available since PHP 7.3.0 and cURL 7.52.0