The curl user survey 2022 is up. Please donate a few minutes of your time and answer a few questions!

curl / libcurl / libcurl API / curl_easy_setopt / all options

All curl_easy_setopt options listed

Related:
info options
multi options
API

All existing options for curl_easy_setopt in alphabetical order.

CURLOPT_ABSTRACT_UNIX_SOCKET	abstract Unix domain socket
CURLOPT_ACCEPTTIMEOUT_MS	timeout waiting for FTP server to connect back
CURLOPT_ACCEPT_ENCODING	automatic decompression of HTTP downloads
CURLOPT_ADDRESS_SCOPE	scope id for IPv6 addresses
CURLOPT_ALTSVC	alt-svc cache file name
CURLOPT_ALTSVC_CTRL	control alt-svc behavior
CURLOPT_APPEND	append to the remote file
CURLOPT_AUTOREFERER	automatically update the referer header
CURLOPT_AWS_SIGV4	V4 signature
CURLOPT_BUFFERSIZE	receive buffer size
CURLOPT_CAINFO	path to Certificate Authority (CA) bundle
CURLOPT_CAINFO_BLOB	Certificate Authority (CA) bundle in PEM format
CURLOPT_CAPATH	directory holding CA certificates
CURLOPT_CERTINFO	request SSL certificate information
CURLOPT_CHUNK_BGN_FUNCTION	callback before a transfer with FTP wildcardmatch
CURLOPT_CHUNK_DATA	pointer passed to the FTP chunk callbacks
CURLOPT_CHUNK_END_FUNCTION	callback after a transfer with FTP wildcardmatch
CURLOPT_CLOSESOCKETDATA	pointer passed to the socket close callback
CURLOPT_CLOSESOCKETFUNCTION	callback to socket close replacement
CURLOPT_CONNECTTIMEOUT	timeout for the connect phase
CURLOPT_CONNECTTIMEOUT_MS	timeout for the connect phase
CURLOPT_CONNECT_ONLY	stop when connected to target server
CURLOPT_CONNECT_TO	connect to a specific host and port instead of the URL's host and port
CURLOPT_CONV_FROM_NETWORK_FUNCTION	convert data from network to host encoding
CURLOPT_CONV_FROM_UTF8_FUNCTION	convert data from UTF8 to host encoding
CURLOPT_CONV_TO_NETWORK_FUNCTION	convert data to network from host encoding
CURLOPT_COOKIE	HTTP Cookie header
CURLOPT_COOKIEFILE	file name to read cookies from
CURLOPT_COOKIEJAR	file name to store cookies to
CURLOPT_COOKIELIST	add to or manipulate cookies held in memory
CURLOPT_COOKIESESSION	start a new cookie session
CURLOPT_COPYPOSTFIELDS	have libcurl copy data to POST
CURLOPT_CRLF	CRLF conversion
CURLOPT_CRLFILE	Certificate Revocation List file
CURLOPT_CURLU	URL in CURLU * format
CURLOPT_CUSTOMREQUEST	custom request method
CURLOPT_DEBUGDATA	pointer passed to the debug callback
CURLOPT_DEBUGFUNCTION	debug callback
CURLOPT_DEFAULT_PROTOCOL	default protocol to use if the URL is missing a
CURLOPT_DIRLISTONLY	ask for names only in a directory listing
CURLOPT_DISALLOW_USERNAME_IN_URL	disallow specifying username in the URL
CURLOPT_DNS_CACHE_TIMEOUT	life-time for DNS cache entries
CURLOPT_DNS_INTERFACE	interface to speak DNS over
CURLOPT_DNS_LOCAL_IP4	IPv4 address to bind DNS resolves to
CURLOPT_DNS_LOCAL_IP6	IPv6 address to bind DNS resolves to
CURLOPT_DNS_SERVERS	DNS servers to use
CURLOPT_DNS_SHUFFLE_ADDRESSES	shuffle IP addresses for hostname
CURLOPT_DNS_USE_GLOBAL_CACHE	global DNS cache
CURLOPT_DOH_SSL_VERIFYHOST	verify the host name in the DoH SSL certificate
CURLOPT_DOH_SSL_VERIFYPEER	verify the DoH SSL certificate
CURLOPT_DOH_SSL_VERIFYSTATUS	verify the DoH SSL certificate's status
CURLOPT_DOH_URL	provide the DNS-over-HTTPS URL
CURLOPT_EGDSOCKET	EGD socket path
CURLOPT_ERRORBUFFER	error buffer for error messages
CURLOPT_EXPECT_100_TIMEOUT_MS	timeout for Expect: 100-continue response
CURLOPT_FAILONERROR	request failure on HTTP response >= 400
CURLOPT_FILETIME	get the modification time of the remote resource
CURLOPT_FNMATCH_DATA	pointer passed to the fnmatch callback
CURLOPT_FNMATCH_FUNCTION	wildcard match callback
CURLOPT_FOLLOWLOCATION	follow HTTP 3xx redirects
CURLOPT_FORBID_REUSE	make connection get closed at once after use
CURLOPT_FRESH_CONNECT	force a new connection to be used
CURLOPT_FTPPORT	make FTP transfer active
CURLOPT_FTPSSLAUTH	order in which to attempt TLS vs SSL
CURLOPT_FTP_ACCOUNT	account info for FTP
CURLOPT_FTP_ALTERNATIVE_TO_USER	command to use instead of USER with FTP
CURLOPT_FTP_CREATE_MISSING_DIRS	create missing dirs for FTP and SFTP
CURLOPT_FTP_FILEMETHOD	select directory traversing method for FTP
CURLOPT_FTP_RESPONSE_TIMEOUT	time allowed to wait for FTP response
CURLOPT_FTP_SKIP_PASV_IP	ignore the IP address in the PASV response
CURLOPT_FTP_SSL_CCC	switch off SSL again with FTP after auth
CURLOPT_FTP_USE_EPRT	use EPRT for FTP
CURLOPT_FTP_USE_EPSV	use EPSV for FTP
CURLOPT_FTP_USE_PRET	use PRET for FTP
CURLOPT_GSSAPI_DELEGATION	allowed GSS-API delegation
CURLOPT_HAPPY_EYEBALLS_TIMEOUT_MS	head start for ipv6 for happy eyeballs
CURLOPT_HAPROXYPROTOCOL	send HAProxy PROXY protocol v1 header
CURLOPT_HEADER	pass headers to the data stream
CURLOPT_HEADERDATA	pointer to pass to header callback
CURLOPT_HEADERFUNCTION	callback that receives header data
CURLOPT_HEADEROPT	send HTTP headers to both proxy and host or separately
CURLOPT_HSTS	HSTS cache file name
CURLOPT_HSTSREADDATA	pointer passed to the HSTS read callback
CURLOPT_HSTSREADFUNCTION	read callback for HSTS hosts
CURLOPT_HSTSWRITEDATA	pointer passed to the HSTS write callback
CURLOPT_HSTSWRITEFUNCTION	write callback for HSTS hosts
CURLOPT_HSTS_CTRL	control HSTS behavior
CURLOPT_HTTP09_ALLOWED	allow HTTP/0.9 response
CURLOPT_HTTP200ALIASES	alternative matches for HTTP 200 OK
CURLOPT_HTTPAUTH	HTTP server authentication methods to try
CURLOPT_HTTPGET	ask for an HTTP GET request
CURLOPT_HTTPHEADER	set of HTTP headers
CURLOPT_HTTPPOST	multipart formpost content
CURLOPT_HTTPPROXYTUNNEL	tunnel through HTTP proxy
CURLOPT_HTTP_CONTENT_DECODING	HTTP content decoding control
CURLOPT_HTTP_TRANSFER_DECODING	HTTP transfer decoding control
CURLOPT_HTTP_VERSION	HTTP protocol version to use
CURLOPT_IGNORE_CONTENT_LENGTH	ignore content length
CURLOPT_INFILESIZE	size of the input file to send off
CURLOPT_INFILESIZE_LARGE	size of the input file to send off
CURLOPT_INTERFACE	source interface for outgoing traffic
CURLOPT_INTERLEAVEDATA	pointer passed to RTSP interleave callback
CURLOPT_INTERLEAVEFUNCTION	callback for RTSP interleaved data
CURLOPT_IOCTLDATA	pointer passed to I/O callback
CURLOPT_IOCTLFUNCTION	callback for I/O operations
CURLOPT_IPRESOLVE	IP protocol version to use
CURLOPT_ISSUERCERT	issuer SSL certificate filename
CURLOPT_ISSUERCERT_BLOB	issuer SSL certificate from memory blob
CURLOPT_KEEP_SENDING_ON_ERROR	keep sending on early HTTP response >= 300
CURLOPT_KEYPASSWD	passphrase to private key
CURLOPT_KRBLEVEL	FTP kerberos security level
CURLOPT_LOCALPORT	local port number to use for socket
CURLOPT_LOCALPORTRANGE	number of additional local ports to try
CURLOPT_LOGIN_OPTIONS	login options
CURLOPT_LOW_SPEED_LIMIT	low speed limit in bytes per second
CURLOPT_LOW_SPEED_TIME	low speed limit time period
CURLOPT_MAIL_AUTH	SMTP authentication address
CURLOPT_MAIL_FROM	SMTP sender address
CURLOPT_MAIL_RCPT	list of SMTP mail recipients
CURLOPT_MAIL_RCPT_ALLLOWFAILS	allow RCPT TO command to fail for some recipients
CURLOPT_MAXAGE_CONN	max idle time allowed for reusing a connection
CURLOPT_MAXCONNECTS	maximum connection cache size
CURLOPT_MAXFILESIZE	maximum file size allowed to download
CURLOPT_MAXFILESIZE_LARGE	maximum file size allowed to download
CURLOPT_MAXLIFETIME_CONN	max lifetime (since creation) allowed for reusing a connection
CURLOPT_MAXREDIRS	maximum number of redirects allowed
CURLOPT_MAX_RECV_SPEED_LARGE	rate limit data download speed
CURLOPT_MAX_SEND_SPEED_LARGE	rate limit data upload speed
CURLOPT_MIMEPOST	send data from mime structure
CURLOPT_MIME_OPTIONS	set MIME option flags
CURLOPT_NETRC	enable use of .netrc
CURLOPT_NETRC_FILE	file name to read .netrc info from
CURLOPT_NEW_DIRECTORY_PERMS	permissions for remotely created directories
CURLOPT_NEW_FILE_PERMS	permissions for remotely created files
CURLOPT_NOBODY	do the download request without getting the body
CURLOPT_NOPROGRESS	switch off the progress meter
CURLOPT_NOPROXY	disable proxy use for specific hosts
CURLOPT_NOSIGNAL	skip all signal handling
CURLOPT_OPENSOCKETDATA	pointer passed to open socket callback
CURLOPT_OPENSOCKETFUNCTION	callback for opening socket
CURLOPT_PASSWORD	password to use in authentication
CURLOPT_PATH_AS_IS	do not handle dot dot sequences
CURLOPT_PINNEDPUBLICKEY	pinned public key
CURLOPT_PIPEWAIT	wait for pipelining/multiplexing
CURLOPT_PORT	remote port number to connect to
CURLOPT_POST	make an HTTP POST
CURLOPT_POSTFIELDS	data to POST to server
CURLOPT_POSTFIELDSIZE	size of POST data pointed to
CURLOPT_POSTFIELDSIZE_LARGE	size of POST data pointed to
CURLOPT_POSTQUOTE	(S)FTP commands to run after the transfer
CURLOPT_POSTREDIR	how to act on an HTTP POST redirect
CURLOPT_PREQUOTE	commands to run before an FTP transfer
CURLOPT_PREREQDATA	pointer passed to the pre-request callback
CURLOPT_PREREQFUNCTION	user callback called when a connection has been
CURLOPT_PRE_PROXY	pre-proxy host to use
CURLOPT_PRIVATE	store a private pointer
CURLOPT_PROGRESSDATA	pointer passed to the progress callback
CURLOPT_PROGRESSFUNCTION	progress meter callback
CURLOPT_PROTOCOLS	allowed protocols
CURLOPT_PROXY	proxy to use
CURLOPT_PROXYAUTH	HTTP proxy authentication methods
CURLOPT_PROXYHEADER	set of HTTP headers to pass to proxy
CURLOPT_PROXYPASSWORD	password to use with proxy authentication
CURLOPT_PROXYPORT	port number the proxy listens on
CURLOPT_PROXYTYPE	proxy protocol type
CURLOPT_PROXYUSERNAME	user name to use for proxy authentication
CURLOPT_PROXYUSERPWD	user name and password to use for proxy authentication
CURLOPT_PROXY_CAINFO	path to proxy Certificate Authority (CA) bundle
CURLOPT_PROXY_CAINFO_BLOB	proxy Certificate Authority (CA) bundle in PEM format
CURLOPT_PROXY_CAPATH	directory holding HTTPS proxy CA certificates
CURLOPT_PROXY_CRLFILE	HTTPS proxy Certificate Revocation List file
CURLOPT_PROXY_ISSUERCERT	proxy issuer SSL certificate filename
CURLOPT_PROXY_ISSUERCERT_BLOB	proxy issuer SSL certificate from memory blob
CURLOPT_PROXY_KEYPASSWD	passphrase for the proxy private key
CURLOPT_PROXY_PINNEDPUBLICKEY	pinned public key for https proxy
CURLOPT_PROXY_SERVICE_NAME	proxy authentication service name
CURLOPT_PROXY_SSLCERT	HTTPS proxy client certificate
CURLOPT_PROXY_SSLCERTTYPE	type of the proxy client SSL certificate
CURLOPT_PROXY_SSLCERT_BLOB	SSL proxy client certificate from memory blob
CURLOPT_PROXY_SSLKEY	private keyfile for HTTPS proxy client cert
CURLOPT_PROXY_SSLKEYTYPE	type of the proxy private key file
CURLOPT_PROXY_SSLKEY_BLOB	private key for proxy cert from memory blob
CURLOPT_PROXY_SSLVERSION	preferred HTTPS proxy TLS version
CURLOPT_PROXY_SSL_CIPHER_LIST	ciphers to use for HTTPS proxy
CURLOPT_PROXY_SSL_OPTIONS	HTTPS proxy SSL behavior options
CURLOPT_PROXY_SSL_VERIFYHOST	verify the proxy certificate's name against host
CURLOPT_PROXY_SSL_VERIFYPEER	verify the proxy's SSL certificate
CURLOPT_PROXY_TLS13_CIPHERS	ciphers suites for proxy TLS 1.3
CURLOPT_PROXY_TLSAUTH_PASSWORD	password to use for proxy TLS authentication
CURLOPT_PROXY_TLSAUTH_TYPE	HTTPS proxy TLS authentication methods
CURLOPT_PROXY_TLSAUTH_USERNAME	user name to use for proxy TLS authentication
CURLOPT_PROXY_TRANSFER_MODE	append FTP transfer mode to URL for proxy
CURLOPT_PUT	make an HTTP PUT request
CURLOPT_QUOTE	(S)FTP commands to run before transfer
CURLOPT_RANDOM_FILE	file to read random data from
CURLOPT_RANGE	byte range to request
CURLOPT_READDATA	pointer passed to the read callback
CURLOPT_READFUNCTION	read callback for data uploads
CURLOPT_REDIR_PROTOCOLS	protocols allowed to redirect to
CURLOPT_REFERER	the HTTP referer header
CURLOPT_REQUEST_TARGET	alternative target for this request
CURLOPT_RESOLVE	provide custom host name to IP address resolves
CURLOPT_RESOLVER_START_DATA	pointer passed to the resolver start callback
CURLOPT_RESOLVER_START_FUNCTION	callback called before a new name resolve is started
CURLOPT_RESUME_FROM	offset to resume transfer from
CURLOPT_RESUME_FROM_LARGE	offset to resume transfer from
CURLOPT_RTSP_CLIENT_CSEQ	RTSP client CSEQ number
CURLOPT_RTSP_REQUEST	RTSP request
CURLOPT_RTSP_SERVER_CSEQ	RTSP server CSEQ number
CURLOPT_RTSP_SESSION_ID	RTSP session ID
CURLOPT_RTSP_STREAM_URI	RTSP stream URI
CURLOPT_RTSP_TRANSPORT	RTSP Transport: header
CURLOPT_SASL_AUTHZID	authorization identity (identity to act as)
CURLOPT_SASL_IR	send initial response in first packet
CURLOPT_SEEKDATA	pointer passed to the seek callback
CURLOPT_SEEKFUNCTION	user callback for seeking in input stream
CURLOPT_SERVICE_NAME	authentication service name
CURLOPT_SHARE	share handle to use
CURLOPT_SOCKOPTDATA	pointer to pass to sockopt callback
CURLOPT_SOCKOPTFUNCTION	callback for setting socket options
CURLOPT_SOCKS5_AUTH	methods for SOCKS5 proxy authentication
CURLOPT_SOCKS5_GSSAPI_NEC	socks proxy gssapi negotiation protection
CURLOPT_SOCKS5_GSSAPI_SERVICE	SOCKS5 proxy authentication service name
CURLOPT_SSH_AUTH_TYPES	auth types for SFTP and SCP
CURLOPT_SSH_COMPRESSION	enable SSH compression
CURLOPT_SSH_HOST_PUBLIC_KEY_MD5	MD5 checksum of SSH server public key
CURLOPT_SSH_HOST_PUBLIC_KEY_SHA256	SHA256 hash of SSH server public key
CURLOPT_SSH_KEYDATA	pointer passed to the SSH key callback
CURLOPT_SSH_KEYFUNCTION	callback for known host matching logic
CURLOPT_SSH_KNOWNHOSTS	file name holding the SSH known hosts
CURLOPT_SSH_PRIVATE_KEYFILE	private key file for SSH auth
CURLOPT_SSH_PUBLIC_KEYFILE	public key file for SSH auth
CURLOPT_SSLCERT	SSL client certificate
CURLOPT_SSLCERTTYPE	type of client SSL certificate
CURLOPT_SSLCERT_BLOB	SSL client certificate from memory blob
CURLOPT_SSLENGINE	SSL engine identifier
CURLOPT_SSLENGINE_DEFAULT	make SSL engine default
CURLOPT_SSLKEY	private keyfile for TLS and SSL client cert
CURLOPT_SSLKEYTYPE	type of the private key file
CURLOPT_SSLKEY_BLOB	private key for client cert from memory blob
CURLOPT_SSLVERSION	preferred TLS/SSL version
CURLOPT_SSL_CIPHER_LIST	ciphers to use for TLS
CURLOPT_SSL_CTX_DATA	pointer passed to ssl_ctx callback
CURLOPT_SSL_CTX_FUNCTION	SSL context callback for OpenSSL, wolfSSL or mbedTLS
CURLOPT_SSL_EC_CURVES	key exchange curves
CURLOPT_SSL_ENABLE_ALPN	Application Layer Protocol Negotiation
CURLOPT_SSL_ENABLE_NPN	use NPN
CURLOPT_SSL_FALSESTART	TLS false start
CURLOPT_SSL_OPTIONS	SSL behavior options
CURLOPT_SSL_SESSIONID_CACHE	use the SSL session-ID cache
CURLOPT_SSL_VERIFYHOST	verify the certificate's name against host
CURLOPT_SSL_VERIFYPEER	verify the peer's SSL certificate
CURLOPT_SSL_VERIFYSTATUS	verify the certificate's status
CURLOPT_STDERR	redirect stderr to another stream
CURLOPT_STREAM_DEPENDS	stream this transfer depends on
CURLOPT_STREAM_DEPENDS_E	stream this transfer depends on exclusively
CURLOPT_STREAM_WEIGHT	numerical stream weight
CURLOPT_SUPPRESS_CONNECT_HEADERS	suppress proxy CONNECT response headers from user callbacks
CURLOPT_TCP_FASTOPEN	TCP Fast Open
CURLOPT_TCP_KEEPALIVE	TCP keep-alive probing
CURLOPT_TCP_KEEPIDLE	TCP keep-alive idle time wait
CURLOPT_TCP_KEEPINTVL	TCP keep-alive interval
CURLOPT_TCP_NODELAY	the TCP_NODELAY option
CURLOPT_TELNETOPTIONS	set of telnet options
CURLOPT_TFTP_BLKSIZE	TFTP block size
CURLOPT_TFTP_NO_OPTIONS	send no TFTP options requests
CURLOPT_TIMECONDITION	select condition for a time request
CURLOPT_TIMEOUT	maximum time the transfer is allowed to complete
CURLOPT_TIMEOUT_MS	maximum time the transfer is allowed to complete
CURLOPT_TIMEVALUE	time value for conditional
CURLOPT_TIMEVALUE_LARGE	time value for conditional
CURLOPT_TLS13_CIPHERS	ciphers suites to use for TLS 1.3
CURLOPT_TLSAUTH_PASSWORD	password to use for TLS authentication
CURLOPT_TLSAUTH_TYPE	TLS authentication methods
CURLOPT_TLSAUTH_USERNAME	user name to use for TLS authentication
CURLOPT_TRAILERDATA	pointer passed to trailing headers callback
CURLOPT_TRAILERFUNCTION	callback for sending trailing headers
CURLOPT_TRANSFERTEXT	request a text based transfer for FTP
CURLOPT_TRANSFER_ENCODING	ask for HTTP Transfer Encoding
CURLOPT_UNIX_SOCKET_PATH	Unix domain socket
CURLOPT_UNRESTRICTED_AUTH	send credentials to other hosts too
CURLOPT_UPKEEP_INTERVAL_MS	connection upkeep interval
CURLOPT_UPLOAD	data upload
CURLOPT_UPLOAD_BUFFERSIZE	upload buffer size
CURLOPT_URL	URL for this transfer
CURLOPT_USERAGENT	HTTP user-agent header
CURLOPT_USERNAME	user name to use in authentication
CURLOPT_USERPWD	user name and password to use in authentication
CURLOPT_USE_SSL	request using SSL / TLS for the transfer
CURLOPT_VERBOSE	verbose mode
CURLOPT_WILDCARDMATCH	directory wildcard transfers
CURLOPT_WRITEDATA	pointer passed to the write callback
CURLOPT_WRITEFUNCTION	callback for writing received data
CURLOPT_XFERINFODATA	pointer passed to the progress callback
CURLOPT_XFERINFOFUNCTION	progress meter callback
CURLOPT_XOAUTH2_BEARER	OAuth 2.0 access token