curl_easy_setopt(3)

NAME
curl_easy_setopt - set options for a curl easy handle

SYNOPSIS
#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLoption option, parameter);

DESCRIPTION
curl_easy_setopt(3) is used to tell libcurl how to behave. By setting the appropriate options, the application can change libcurl's behavior. All options are set with an option followed by a parameter. That parameter can be a long, a function pointer, an object pointer or a curl_off_t, depending on what the specific option expects. Read this manual carefully as bad input values may cause libcurl to behave badly! You can only set one option in each function call. A typical application uses many curl_easy_setopt(3) calls in the setup phase. Options set with this function call are valid for all forthcoming transfers performed using this handle. The options are not in any way reset between transfers, so if you want subsequent transfers with different options, you must change them between the transfers. You can optionally reset all options back to internal default with curl_easy_reset(3). Strings passed to libcurl as 'char *' arguments, are copied by the library; thus the string storage associated to the pointer argument may be overwritten after curl_easy_setopt(3) returns. The only exception to this rule is really CURLOPT_POSTFIELDS(3), but the alternative that copies the string CURLOPT_COPYPOSTFIELDS(3) has some usage characteristics you need to read up on. The order in which the options are set does not matter. Before version 7.17.0, strings were not copied. Instead the user was forced keep them available until libcurl no longer needed them. The handle is the return code from a curl_easy_init(3) or curl_easy_duphandle(3) call.

BEHAVIOR OPTIONS

CURLOPT_VERBOSE
    Display verbose information. See CURLOPT_VERBOSE(3)

CURLOPT_HEADER
    Include the header in the body output. See CURLOPT_HEADER(3)

CURLOPT_NOPROGRESS
    Shut off the progress meter. See CURLOPT_NOPROGRESS(3)

CURLOPT_NOSIGNAL
    Do not install signal handlers. See CURLOPT_NOSIGNAL(3)

CURLOPT_WILDCARDMATCH
    Transfer multiple files according to a file name pattern. See CURLOPT_WILDCARDMATCH(3)

CALLBACK OPTIONS

CURLOPT_WRITEFUNCTION
    Callback for writing data. See CURLOPT_WRITEFUNCTION(3)

CURLOPT_WRITEDATA
    Data pointer to pass to the write callback. See CURLOPT_WRITEDATA(3)

CURLOPT_READFUNCTION
    Callback for reading data. See CURLOPT_READFUNCTION(3)

CURLOPT_READDATA
    Data pointer to pass to the read callback. See CURLOPT_READDATA(3)

CURLOPT_IOCTLFUNCTION
    Callback for I/O operations. See CURLOPT_IOCTLFUNCTION(3)

CURLOPT_IOCTLDATA
    Data pointer to pass to the I/O callback. See CURLOPT_IOCTLDATA(3)

CURLOPT_SEEKFUNCTION
    Callback for seek operations. See CURLOPT_SEEKFUNCTION(3)

CURLOPT_SEEKDATA
    Data pointer to pass to the seek callback. See CURLOPT_SEEKDATA(3)

CURLOPT_SOCKOPTFUNCTION
    Callback for sockopt operations. See CURLOPT_SOCKOPTFUNCTION(3)

CURLOPT_SOCKOPTDATA
    Data pointer to pass to the sockopt callback. See CURLOPT_SOCKOPTDATA(3)

CURLOPT_OPENSOCKETFUNCTION
    Callback for socket creation. See CURLOPT_OPENSOCKETFUNCTION(3)

CURLOPT_OPENSOCKETDATA
    Data pointer to pass to the open socket callback. See CURLOPT_OPENSOCKETDATA(3)

CURLOPT_CLOSESOCKETFUNCTION
    Callback for closing socket. See CURLOPT_CLOSESOCKETFUNCTION(3)

CURLOPT_CLOSESOCKETDATA
    Data pointer to pass to the close socket callback. See CURLOPT_CLOSESOCKETDATA(3)

CURLOPT_PROGRESSFUNCTION
    OBSOLETE callback for progress meter. See CURLOPT_PROGRESSFUNCTION(3)

CURLOPT_PROGRESSDATA
    Data pointer to pass to the progress meter callback. See CURLOPT_PROGRESSDATA(3)

CURLOPT_XFERINFOFUNCTION
    Callback for progress meter. See CURLOPT_XFERINFOFUNCTION(3)

CURLOPT_XFERINFODATA
    Data pointer to pass to the progress meter callback. See CURLOPT_XFERINFODATA(3)

CURLOPT_HEADERFUNCTION
    Callback for writing received headers. See CURLOPT_HEADERFUNCTION(3)

CURLOPT_HEADERDATA
    Data pointer to pass to the header callback. See CURLOPT_HEADERDATA(3)

CURLOPT_DEBUGFUNCTION
    Callback for debug information. See CURLOPT_DEBUGFUNCTION(3)

CURLOPT_DEBUGDATA
    Data pointer to pass to the debug callback. See CURLOPT_DEBUGDATA(3)

CURLOPT_SSL_CTX_FUNCTION
    Callback for SSL context logic. See CURLOPT_SSL_CTX_FUNCTION(3)

CURLOPT_SSL_CTX_DATA
    Data pointer to pass to the SSL context callback. See CURLOPT_SSL_CTX_DATA(3)

CURLOPT_CONV_TO_NETWORK_FUNCTION
    Callback for code base conversion. See CURLOPT_CONV_TO_NETWORK_FUNCTION(3)

CURLOPT_CONV_FROM_NETWORK_FUNCTION
    Callback for code base conversion. See CURLOPT_CONV_FROM_NETWORK_FUNCTION(3)

CURLOPT_CONV_FROM_UTF8_FUNCTION
    Callback for code base conversion. See CURLOPT_CONV_FROM_UTF8_FUNCTION(3)

CURLOPT_INTERLEAVEFUNCTION
    Callback for RTSP interleaved data. See CURLOPT_INTERLEAVEFUNCTION(3)

CURLOPT_INTERLEAVEDATA
    Data pointer to pass to the RTSP interleave callback. See CURLOPT_INTERLEAVEDATA(3)

CURLOPT_CHUNK_BGN_FUNCTION
    Callback for wildcard download start of chunk. See CURLOPT_CHUNK_BGN_FUNCTION(3)

CURLOPT_CHUNK_END_FUNCTION
    Callback for wildcard download end of chunk. See CURLOPT_CHUNK_END_FUNCTION(3)

CURLOPT_CHUNK_DATA
    Data pointer to pass to the chunk callbacks. See CURLOPT_CHUNK_DATA(3)

CURLOPT_FNMATCH_FUNCTION
    Callback for wildcard matching. See CURLOPT_FNMATCH_FUNCTION(3)

CURLOPT_FNMATCH_DATA
    Data pointer to pass to the wildcard matching callback. See CURLOPT_FNMATCH_DATA(3)

ERROR OPTIONS

CURLOPT_ERRORBUFFER
    Error message buffer. See CURLOPT_ERRORBUFFER(3)

CURLOPT_STDERR
    stderr replacement stream. See CURLOPT_STDERR(3)

CURLOPT_FAILONERROR
    Fail on HTTP 4xx errors. CURLOPT_FAILONERROR(3)

NETWORK OPTIONS

CURLOPT_URL
    URL to work on. See CURLOPT_URL(3)

CURLOPT_PATH_AS_IS
    Disable squashing /../ and /./ sequences in the path. See CURLOPT_PATH_AS_IS(3)

CURLOPT_PROTOCOLS
    Allowed protocols. See CURLOPT_PROTOCOLS(3)

CURLOPT_REDIR_PROTOCOLS
    Protocols to allow redirects to. See CURLOPT_REDIR_PROTOCOLS(3)

CURLOPT_DEFAULT_PROTOCOL
    Default protocol. See CURLOPT_DEFAULT_PROTOCOL(3)

CURLOPT_PROXY
    Proxy to use. See CURLOPT_PROXY(3)

CURLOPT_PROXYPORT
    Proxy port to use. See CURLOPT_PROXYPORT(3)

CURLOPT_PROXYTYPE
    Proxy type. See CURLOPT_PROXYTYPE(3)

CURLOPT_NOPROXY
    Filter out hosts from proxy use. CURLOPT_NOPROXY(3)

CURLOPT_HTTPPROXYTUNNEL
    Tunnel through the HTTP proxy. CURLOPT_HTTPPROXYTUNNEL(3)

CURLOPT_SOCKS5_GSSAPI_SERVICE
    Socks5 GSSAPI service name. CURLOPT_SOCKS5_GSSAPI_SERVICE(3)

CURLOPT_SOCKS5_GSSAPI_NEC
    Socks5 GSSAPI NEC mode. See CURLOPT_SOCKS5_GSSAPI_NEC(3)

CURLOPT_PROXY_SERVICE_NAME
    Proxy authentication service name. CURLOPT_PROXY_SERVICE_NAME(3)

CURLOPT_SERVICE_NAME
    Authentication service name. CURLOPT_SERVICE_NAME(3)

CURLOPT_INTERFACE
    Bind connection locally to this. See CURLOPT_INTERFACE(3)

CURLOPT_LOCALPORT
    Bind connection locally to this port. See CURLOPT_LOCALPORT(3)

CURLOPT_LOCALPORTRANGE
    Bind connection locally to port range. See CURLOPT_LOCALPORTRANGE(3)

CURLOPT_DNS_CACHE_TIMEOUT
    Timeout for DNS cache. See CURLOPT_DNS_CACHE_TIMEOUT(3)

CURLOPT_DNS_USE_GLOBAL_CACHE
    OBSOLETE Enable global DNS cache. See CURLOPT_DNS_USE_GLOBAL_CACHE(3)

CURLOPT_BUFFERSIZE
    Ask for smaller buffer size. See CURLOPT_BUFFERSIZE(3)

CURLOPT_PORT
    Port number to connect to. See CURLOPT_PORT(3)

CURLOPT_TCP_NODELAY
    Disable the Nagle algorithm. See CURLOPT_TCP_NODELAY(3)

CURLOPT_ADDRESS_SCOPE
    IPv6 scope for local addresses. See CURLOPT_ADDRESS_SCOPE(3)

CURLOPT_TCP_KEEPALIVE
    Enable TCP keep-alive. See CURLOPT_TCP_KEEPALIVE(3)

CURLOPT_TCP_KEEPIDLE
    Idle time before sending keep-alive. See CURLOPT_TCP_KEEPIDLE(3)

CURLOPT_TCP_KEEPINTVL
    Interval between keep-alive probes. See CURLOPT_TCP_KEEPINTVL(3)

CURLOPT_UNIX_SOCKET_PATH
    Path to a Unix domain socket. See CURLOPT_UNIX_SOCKET_PATH(3)

NAMES and PASSWORDS OPTIONS (Authentication)

CURLOPT_NETRC
    Enable .netrc parsing. See CURLOPT_NETRC(3)

CURLOPT_NETRC_FILE
    .netrc file name. See CURLOPT_NETRC_FILE(3)

CURLOPT_USERPWD
    User name and password. See CURLOPT_USERPWD(3)

CURLOPT_PROXYUSERPWD
    Proxy user name and password. See CURLOPT_PROXYUSERPWD(3)

CURLOPT_USERNAME
    User name. See CURLOPT_USERNAME(3)

CURLOPT_PASSWORD
    Password. See CURLOPT_PASSWORD(3)

CURLOPT_LOGIN_OPTIONS
    Login options. See CURLOPT_LOGIN_OPTIONS(3)

CURLOPT_PROXYUSERNAME
    Proxy user name. See CURLOPT_PROXYUSERNAME(3)

CURLOPT_PROXYPASSWORD
    Proxy password. See CURLOPT_PROXYPASSWORD(3)

CURLOPT_HTTPAUTH
    HTTP server authentication methods. See CURLOPT_HTTPAUTH(3)

CURLOPT_TLSAUTH_USERNAME
    TLS authentication user name. See CURLOPT_TLSAUTH_USERNAME(3)

CURLOPT_TLSAUTH_PASSWORD
    TLS authentication password. See CURLOPT_TLSAUTH_PASSWORD(3)

CURLOPT_TLSAUTH_TYPE
    TLS authentication methods. See CURLOPT_TLSAUTH_TYPE(3)

CURLOPT_PROXYAUTH
    HTTP proxy authentication methods. See CURLOPT_PROXYAUTH(3)

CURLOPT_SASL_IR
    Enable SASL initial response. See CURLOPT_SASL_IR(3)

CURLOPT_XOAUTH2_BEARER
    OAuth2 bearer token. See CURLOPT_XOAUTH2_BEARER(3)

HTTP OPTIONS

CURLOPT_AUTOREFERER
    Automatically set Referer: header. See CURLOPT_AUTOREFERER(3)

CURLOPT_ACCEPT_ENCODING
    Accept-Encoding and automatic decompressing data. See CURLOPT_ACCEPT_ENCODING(3)

CURLOPT_TRANSFER_ENCODING
    Request Transfer-Encoding. See CURLOPT_TRANSFER_ENCODING(3)

CURLOPT_FOLLOWLOCATION
    Follow HTTP redirects. See CURLOPT_FOLLOWLOCATION(3)

CURLOPT_UNRESTRICTED_AUTH
    Do not restrict authentication to original host. CURLOPT_UNRESTRICTED_AUTH(3)

CURLOPT_MAXREDIRS
    Maximum number of redirects to follow. See CURLOPT_MAXREDIRS(3)

CURLOPT_POSTREDIR
    How to act on redirects after POST. See CURLOPT_POSTREDIR(3)

CURLOPT_PUT
    Issue a HTTP PUT request. See CURLOPT_PUT(3)

CURLOPT_POST
    Issue a HTTP POST request. See CURLOPT_POST(3)

CURLOPT_POSTFIELDS
    Send a POST with this data. See CURLOPT_POSTFIELDS(3)

CURLOPT_POSTFIELDSIZE
    The POST data is this big. See CURLOPT_POSTFIELDSIZE(3)

CURLOPT_POSTFIELDSIZE_LARGE
    The POST data is this big. See CURLOPT_POSTFIELDSIZE_LARGE(3)

CURLOPT_COPYPOSTFIELDS
    Send a POST with this data - and copy it. See CURLOPT_COPYPOSTFIELDS(3)

CURLOPT_HTTPPOST
    Multipart formpost HTTP POST. See CURLOPT_HTTPPOST(3)

CURLOPT_REFERER
    Referer: header. See CURLOPT_REFERER(3)

CURLOPT_USERAGENT
    User-Agent: header. See CURLOPT_USERAGENT(3)

CURLOPT_HTTPHEADER
    Custom HTTP headers. See CURLOPT_HTTPHEADER(3)

CURLOPT_HEADEROPT
    Control custom headers. See CURLOPT_HEADEROPT(3)

CURLOPT_PROXYHEADER
    Custom HTTP headers sent to proxy. See CURLOPT_PROXYHEADER(3)

CURLOPT_HTTP200ALIASES
    Alternative versions of 200 OK. See CURLOPT_HTTP200ALIASES(3)

CURLOPT_COOKIE
    Cookie(s) to send. See CURLOPT_COOKIE(3)

CURLOPT_COOKIEFILE
    File to read cookies from. See CURLOPT_COOKIEFILE(3)

CURLOPT_COOKIEJAR
    File to write cookies to. See CURLOPT_COOKIEJAR(3)

CURLOPT_COOKIESESSION
    Start a new cookie session. See CURLOPT_COOKIESESSION(3)

CURLOPT_COOKIELIST
    Add or control cookies. See CURLOPT_COOKIELIST(3)

CURLOPT_HTTPGET
    Do a HTTP GET request. See CURLOPT_HTTPGET(3)

CURLOPT_HTTP_VERSION
    HTTP version to use. CURLOPT_HTTP_VERSION(3)

CURLOPT_IGNORE_CONTENT_LENGTH
    Ignore Content-Length. See CURLOPT_IGNORE_CONTENT_LENGTH(3)

CURLOPT_HTTP_CONTENT_DECODING
    Disable Content decoding. See CURLOPT_HTTP_CONTENT_DECODING(3)

CURLOPT_HTTP_TRANSFER_DECODING
    Disable Transfer decoding. See CURLOPT_HTTP_TRANSFER_DECODING(3)

CURLOPT_EXPECT_100_TIMEOUT_MS
    100-continue timeout. See CURLOPT_EXPECT_100_TIMEOUT_MS(3)

CURLOPT_PIPEWAIT
    Wait on connection to pipeline on it. See CURLOPT_PIPEWAIT(3)

CURLOPT_STREAM_DEPENDS
    This HTTP/2 stream depends on another. See CURLOPT_STREAM_DEPENDS(3)

CURLOPT_STREAM_DEPENDS_E
    This HTTP/2 stream depends on another exclusively. See CURLOPT_STREAM_DEPENDS_E(3)

CURLOPT_STREAM_WEIGHT
    Set this HTTP/2 stream's weight. See CURLOPT_STREAM_WEIGHT(3)

SMTP OPTIONS

CURLOPT_MAIL_FROM
    Address of the sender. See CURLOPT_MAIL_FROM(3)

CURLOPT_MAIL_RCPT
    Address of the recipients. See CURLOPT_MAIL_RCPT(3)

CURLOPT_MAIL_AUTH
    Authentication address. See CURLOPT_MAIL_AUTH(3)

TFTP OPTIONS

CURLOPT_TFTP_BLKSIZE
    TFTP block size. See CURLOPT_TFTP_BLKSIZE(3)

CURLOPT_TFTP_NO_OPTIONS
    Do not send TFTP options requests. See CURLOPT_TFTP_NO_OPTIONS(3)

FTP OPTIONS

CURLOPT_FTPPORT
    Use active FTP. See CURLOPT_FTPPORT(3)

CURLOPT_QUOTE
    Commands to run before transfer. See CURLOPT_QUOTE(3)

CURLOPT_POSTQUOTE
    Commands to run after transfer. See CURLOPT_POSTQUOTE(3)

CURLOPT_PREQUOTE
    Commands to run just before transfer. See CURLOPT_PREQUOTE(3)

CURLOPT_APPEND
    Append to remote file. See CURLOPT_APPEND(3)

CURLOPT_FTP_USE_EPRT
    Use EPTR. See CURLOPT_FTP_USE_EPRT(3)

CURLOPT_FTP_USE_EPSV
    Use EPSV. See CURLOPT_FTP_USE_EPSV(3)

CURLOPT_FTP_USE_PRET
    Use PRET. See CURLOPT_FTP_USE_PRET(3)

CURLOPT_FTP_CREATE_MISSING_DIRS
    Create missing directories on the remote server. See CURLOPT_FTP_CREATE_MISSING_DIRS(3)

CURLOPT_FTP_RESPONSE_TIMEOUT
    Timeout for FTP responses. See CURLOPT_FTP_RESPONSE_TIMEOUT(3)

CURLOPT_FTP_ALTERNATIVE_TO_USER
    Alternative to USER. See CURLOPT_FTP_ALTERNATIVE_TO_USER(3)

CURLOPT_FTP_SKIP_PASV_IP
    Ignore the IP address in the PASV response. See CURLOPT_FTP_SKIP_PASV_IP(3)

CURLOPT_FTPSSLAUTH
    Control how to do TLS. See CURLOPT_FTPSSLAUTH(3)

CURLOPT_FTP_SSL_CCC
    Back to non-TLS again after authentication. See CURLOPT_FTP_SSL_CCC(3)

CURLOPT_FTP_ACCOUNT
    Send ACCT command. See CURLOPT_FTP_ACCOUNT(3)

CURLOPT_FTP_FILEMETHOD
    Specify how to reach files. See CURLOPT_FTP_FILEMETHOD(3)

RTSP OPTIONS

CURLOPT_RTSP_REQUEST
    RTSP request. See CURLOPT_RTSP_REQUEST(3)

CURLOPT_RTSP_SESSION_ID
    RTSP session-id. See CURLOPT_RTSP_SESSION_ID(3)

CURLOPT_RTSP_STREAM_URI
    RTSP stream URI. See CURLOPT_RTSP_STREAM_URI(3)

CURLOPT_RTSP_TRANSPORT
    RTSP Transport: header. See CURLOPT_RTSP_TRANSPORT(3)

CURLOPT_RTSP_CLIENT_CSEQ
    Client CSEQ number. See CURLOPT_RTSP_CLIENT_CSEQ(3)

CURLOPT_RTSP_SERVER_CSEQ
    CSEQ number for RTSP Server->Client request. See CURLOPT_RTSP_SERVER_CSEQ(3)

PROTOCOL OPTIONS

CURLOPT_TRANSFERTEXT
    Use text transfer. See CURLOPT_TRANSFERTEXT(3)

CURLOPT_PROXY_TRANSFER_MODE
    Add transfer mode to URL over proxy. See CURLOPT_PROXY_TRANSFER_MODE(3)

CURLOPT_CRLF
    Convert newlines. See CURLOPT_CRLF(3)

CURLOPT_RANGE
    Range requests. See CURLOPT_RANGE(3)

CURLOPT_RESUME_FROM
    Resume a transfer. See CURLOPT_RESUME_FROM(3)

CURLOPT_RESUME_FROM_LARGE
    Resume a transfer. See CURLOPT_RESUME_FROM_LARGE(3)

CURLOPT_CUSTOMREQUEST
    Custom request/method. See CURLOPT_CUSTOMREQUEST(3)

CURLOPT_FILETIME
    Request file modification date and time. See CURLOPT_FILETIME(3)

CURLOPT_DIRLISTONLY
    List only. See CURLOPT_DIRLISTONLY(3)

CURLOPT_NOBODY
    Do not get the body contents. See CURLOPT_NOBODY(3)

CURLOPT_INFILESIZE
    Size of file to send. CURLOPT_INFILESIZE(3)

CURLOPT_INFILESIZE_LARGE
    Size of file to send. CURLOPT_INFILESIZE_LARGE(3)

CURLOPT_UPLOAD
    Upload data. See CURLOPT_UPLOAD(3)

CURLOPT_MAXFILESIZE
    Maximum file size to get. See CURLOPT_MAXFILESIZE(3)

CURLOPT_MAXFILESIZE_LARGE
    Maximum file size to get. See CURLOPT_MAXFILESIZE_LARGE(3)

CURLOPT_TIMECONDITION
    Make a time conditional request. See CURLOPT_TIMECONDITION(3)

CURLOPT_TIMEVALUE
    Time value for the time conditional request. See CURLOPT_TIMEVALUE(3)

CONNECTION OPTIONS

CURLOPT_TIMEOUT
    Timeout for the entire request. See CURLOPT_TIMEOUT(3)

CURLOPT_TIMEOUT_MS
    Millisecond timeout for the entire request. See CURLOPT_TIMEOUT_MS(3)

CURLOPT_LOW_SPEED_LIMIT
    Low speed limit to abort transfer. See CURLOPT_LOW_SPEED_LIMIT(3)

CURLOPT_LOW_SPEED_TIME
    Time to be below the speed to trigger low speed abort. See CURLOPT_LOW_SPEED_TIME(3)

CURLOPT_MAX_SEND_SPEED_LARGE
    Cap the upload speed to this. See CURLOPT_MAX_SEND_SPEED_LARGE(3)

CURLOPT_MAX_RECV_SPEED_LARGE
    Cap the download speed to this. See CURLOPT_MAX_RECV_SPEED_LARGE(3)

CURLOPT_MAXCONNECTS
    Maximum number of connections in the connection pool. See CURLOPT_MAXCONNECTS(3)

CURLOPT_FRESH_CONNECT
    Use a new connection. CURLOPT_FRESH_CONNECT(3)

CURLOPT_FORBID_REUSE
    Prevent subsequent connections from re-using this. See CURLOPT_FORBID_REUSE(3)

CURLOPT_CONNECTTIMEOUT
    Timeout for the connection phase. See CURLOPT_CONNECTTIMEOUT(3)

CURLOPT_CONNECTTIMEOUT_MS
    Millisecond timeout for the connection phase. See CURLOPT_CONNECTTIMEOUT_MS(3)

CURLOPT_IPRESOLVE
    IP version to resolve to. See CURLOPT_IPRESOLVE(3)

CURLOPT_CONNECT_ONLY
    Only connect, nothing else. See CURLOPT_CONNECT_ONLY(3)

CURLOPT_USE_SSL
    Use TLS/SSL. See CURLOPT_USE_SSL(3)

CURLOPT_RESOLVE
    Provide fixed/fake name resolves. See CURLOPT_RESOLVE(3)

CURLOPT_DNS_INTERFACE
    Bind name resolves to this interface. See CURLOPT_DNS_INTERFACE(3)

CURLOPT_DNS_LOCAL_IP4
    Bind name resolves to this IP4 address. See CURLOPT_DNS_LOCAL_IP4(3)

CURLOPT_DNS_LOCAL_IP6
    Bind name resolves to this IP6 address. See CURLOPT_DNS_LOCAL_IP6(3)

CURLOPT_DNS_SERVERS
    Preferred DNS servers. See CURLOPT_DNS_SERVERS(3)

CURLOPT_ACCEPTTIMEOUT_MS
    Timeout for waiting for the server's connect back to be accepted. See CURLOPT_ACCEPTTIMEOUT_MS(3)

SSL and SECURITY OPTIONS

CURLOPT_SSLCERT
    Client cert. See CURLOPT_SSLCERT(3)

CURLOPT_SSLCERTTYPE
    Client cert type. See CURLOPT_SSLCERTTYPE(3)

CURLOPT_SSLKEY
    Client key. See CURLOPT_SSLKEY(3)

CURLOPT_SSLKEYTYPE
    Client key type. See CURLOPT_SSLKEYTYPE(3)

CURLOPT_KEYPASSWD
    Client key password. See CURLOPT_KEYPASSWD(3)

CURLOPT_SSL_ENABLE_ALPN
    Enable use of ALPN. See CURLOPT_SSL_ENABLE_ALPN(3)

CURLOPT_SSL_ENABLE_NPN
    Enable use of NPN. See CURLOPT_SSL_ENABLE_NPN(3)

CURLOPT_SSLENGINE
    Use identifier with SSL engine. See CURLOPT_SSLENGINE(3)

CURLOPT_SSLENGINE_DEFAULT
    Default SSL engine. See CURLOPT_SSLENGINE_DEFAULT(3)

CURLOPT_SSL_FALSESTART
    Enable TLS False Start. See CURLOPT_SSL_FALSESTART(3)

CURLOPT_SSLVERSION
    SSL version to use. See CURLOPT_SSLVERSION(3)

CURLOPT_SSL_VERIFYHOST
    Verify the host name in the SSL certificate. See CURLOPT_SSL_VERIFYHOST(3)

CURLOPT_SSL_VERIFYPEER
    Verify the SSL certificate. See CURLOPT_SSL_VERIFYPEER(3)

CURLOPT_SSL_VERIFYSTATUS
    Verify the SSL certificate's status. See CURLOPT_SSL_VERIFYSTATUS(3)

CURLOPT_CAINFO
    CA cert bundle. See CURLOPT_CAINFO(3)

CURLOPT_ISSUERCERT
    Issuer certificate. See CURLOPT_ISSUERCERT(3)

CURLOPT_CAPATH
    Path to CA cert bundle. See CURLOPT_CAPATH(3)

CURLOPT_CRLFILE
    Certificate Revocation List. See CURLOPT_CRLFILE(3)

CURLOPT_CERTINFO
    Extract certificate info. See CURLOPT_CERTINFO(3)

CURLOPT_PINNEDPUBLICKEY
    Set pinned SSL public key . See CURLOPT_PINNEDPUBLICKEY(3)

CURLOPT_RANDOM_FILE
    Provide source for entropy random data. See CURLOPT_RANDOM_FILE(3)

CURLOPT_EGDSOCKET
    Identify EGD socket for entropy. See CURLOPT_EGDSOCKET(3)

CURLOPT_SSL_CIPHER_LIST
    Ciphers to use. See CURLOPT_SSL_CIPHER_LIST(3)

CURLOPT_SSL_SESSIONID_CACHE
    Disable SSL session-id cache. See CURLOPT_SSL_SESSIONID_CACHE(3)

CURLOPT_SSL_OPTIONS
    Control SSL behavior. See CURLOPT_SSL_OPTIONS(3)

CURLOPT_KRBLEVEL
    Kerberos security level. See CURLOPT_KRBLEVEL(3)

CURLOPT_GSSAPI_DELEGATION
    Disable GSS-API delegation. See CURLOPT_GSSAPI_DELEGATION(3)

SSH OPTIONS

CURLOPT_SSH_AUTH_TYPES
    SSH authentication types. See CURLOPT_SSH_AUTH_TYPES(3)

CURLOPT_SSH_HOST_PUBLIC_KEY_MD5
    MD5 of host's public key. See CURLOPT_SSH_HOST_PUBLIC_KEY_MD5(3)

CURLOPT_SSH_PUBLIC_KEYFILE
    File name of public key. See CURLOPT_SSH_PUBLIC_KEYFILE(3)

CURLOPT_SSH_PRIVATE_KEYFILE
    File name of private key. See CURLOPT_SSH_PRIVATE_KEYFILE(3)

CURLOPT_SSH_KNOWNHOSTS
    File name with known hosts. See CURLOPT_SSH_KNOWNHOSTS(3)

CURLOPT_SSH_KEYFUNCTION
    Callback for known hosts handling. See CURLOPT_SSH_KEYFUNCTION(3)

CURLOPT_SSH_KEYDATA
    Custom pointer to pass to ssh key callback. See CURLOPT_SSH_KEYDATA(3)

OTHER OPTIONS

CURLOPT_PRIVATE
    Private pointer to store. See CURLOPT_PRIVATE(3)

CURLOPT_SHARE
    Share object to use. See CURLOPT_SHARE(3)

CURLOPT_NEW_FILE_PERMS
    Mode for creating new remote files. See CURLOPT_NEW_FILE_PERMS(3)

CURLOPT_NEW_DIRECTORY_PERMS
    Mode for creating new remote directories. See CURLOPT_NEW_DIRECTORY_PERMS(3)

TELNET OPTIONS

CURLOPT_TELNETOPTIONS
    TELNET options. See CURLOPT_TELNETOPTIONS(3)

RETURN VALUE
CURLE_OK (zero) means that the option was set properly, non-zero means an error occurred as <curl/curl.h> defines. See the libcurl-errors(3) man page for the full list with descriptions. If you try to set an option that libcurl doesn't know about, perhaps because the library is too old to support it or the option was removed in a recent version, this function will return CURLE_UNKNOWN_OPTION. If support for the option was disabled at compile-time, it will return CURLE_NOT_BUILT_IN.

EXAMPLE
CURL *curl = curl_easy_init();
if(curl) {
  CURLcode res;
  curl_easy_setopt(curl, CURLOPT_URL, "http://example.com");
  res = curl_easy_perform(curl);
  curl_easy_cleanup(curl);
}

SEE ALSO
curl_easy_init(3), curl_easy_cleanup(3), curl_easy_reset(3), curl_easy_getinfo(3), curl_multi_setopt(3),