Lines Matching refs:See

7 See-also:
67 Display verbose information. See CURLOPT_VERBOSE(3)
71 Include the header in the body output. See CURLOPT_HEADER(3)
75 Shut off the progress meter. See CURLOPT_NOPROGRESS(3)
79 Do not install signal handlers. See CURLOPT_NOSIGNAL(3)
83 Transfer multiple files according to a filename pattern. See
90 Callback for writing data. See CURLOPT_WRITEFUNCTION(3)
94 Data pointer to pass to the write callback. See CURLOPT_WRITEDATA(3)
98 Callback for reading data. See CURLOPT_READFUNCTION(3)
102 Data pointer to pass to the read callback. See CURLOPT_READDATA(3)
107 See CURLOPT_IOCTLFUNCTION(3)
112 See CURLOPT_IOCTLDATA(3)
116 Callback for seek operations. See CURLOPT_SEEKFUNCTION(3)
120 Data pointer to pass to the seek callback. See CURLOPT_SEEKDATA(3)
124 Callback for sockopt operations. See CURLOPT_SOCKOPTFUNCTION(3)
128 Data pointer to pass to the sockopt callback. See CURLOPT_SOCKOPTDATA(3)
132 Callback for socket creation. See CURLOPT_OPENSOCKETFUNCTION(3)
136 Data pointer to pass to the open socket callback. See CURLOPT_OPENSOCKETDATA(3)
140 Callback for closing socket. See CURLOPT_CLOSESOCKETFUNCTION(3)
144 Data pointer to pass to the close socket callback. See CURLOPT_CLOSESOCKETDATA(3)
149 See CURLOPT_PROGRESSFUNCTION(3)
153 Data pointer to pass to the progress meter callback. See CURLOPT_PROGRESSDATA(3)
157 Callback for progress meter. See CURLOPT_XFERINFOFUNCTION(3)
161 Data pointer to pass to the progress meter callback. See CURLOPT_XFERINFODATA(3)
165 Callback for writing received headers. See CURLOPT_HEADERFUNCTION(3)
169 Data pointer to pass to the header callback. See CURLOPT_HEADERDATA(3)
173 Callback for debug information. See CURLOPT_DEBUGFUNCTION(3)
177 Data pointer to pass to the debug callback. See CURLOPT_DEBUGDATA(3)
181 Callback for SSL context logic. See CURLOPT_SSL_CTX_FUNCTION(3)
185 Data pointer to pass to the SSL context callback. See CURLOPT_SSL_CTX_DATA(3)
190 See CURLOPT_CONV_TO_NETWORK_FUNCTION(3)
195 See CURLOPT_CONV_FROM_NETWORK_FUNCTION(3)
200 See CURLOPT_CONV_FROM_UTF8_FUNCTION(3)
204 Callback for RTSP interleaved data. See CURLOPT_INTERLEAVEFUNCTION(3)
208 Data pointer to pass to the RTSP interleave callback. See CURLOPT_INTERLEAVEDATA(3)
212 Callback for wildcard download start of chunk. See CURLOPT_CHUNK_BGN_FUNCTION(3)
216 Callback for wildcard download end of chunk. See CURLOPT_CHUNK_END_FUNCTION(3)
220 Data pointer to pass to the chunk callbacks. See CURLOPT_CHUNK_DATA(3)
224 Callback for wildcard matching. See CURLOPT_FNMATCH_FUNCTION(3)
228 Data pointer to pass to the wildcard matching callback. See CURLOPT_FNMATCH_DATA(3)
232 Suppress proxy CONNECT response headers from user callbacks. See
237 Callback to be called before a new resolve request is started. See
242 Data pointer to pass to resolver start callback. See CURLOPT_RESOLVER_START_DATA(3)
247 is made on that connection. See CURLOPT_PREREQFUNCTION(3)
251 Data pointer to pass to the CURLOPT_PREREQFUNCTION callback. See
258 Error message buffer. See CURLOPT_ERRORBUFFER(3)
262 stderr replacement stream. See CURLOPT_STDERR(3)
276 URL to work on. See CURLOPT_URL(3)
280 Disable squashing /../ and /./ sequences in the path. See CURLOPT_PATH_AS_IS(3)
284 **Deprecated option** Allowed protocols. See CURLOPT_PROTOCOLS(3)
288 Allowed protocols. See CURLOPT_PROTOCOLS_STR(3)
292 **Deprecated option** Protocols to allow redirects to. See
297 Protocols to allow redirects to. See CURLOPT_REDIR_PROTOCOLS_STR(3)
301 Default protocol. See CURLOPT_DEFAULT_PROTOCOL(3)
305 Proxy to use. See CURLOPT_PROXY(3)
309 Socks proxy to use. See CURLOPT_PRE_PROXY(3)
313 Proxy port to use. See CURLOPT_PROXYPORT(3)
317 Proxy type. See CURLOPT_PROXYTYPE(3)
329 Connect to a specific host and port. See CURLOPT_CONNECT_TO(3)
333 Socks5 authentication methods. See CURLOPT_SOCKS5_AUTH(3)
338 See CURLOPT_SOCKS5_GSSAPI_SERVICE(3)
342 Socks5 GSSAPI NEC mode. See CURLOPT_SOCKS5_GSSAPI_NEC(3)
350 Send an HAProxy PROXY protocol v1 header. See CURLOPT_HAPROXYPROTOCOL(3)
354 Spoof the client IP in an HAProxy PROXY protocol v1 header. See
363 Bind connection locally to this. See CURLOPT_INTERFACE(3)
367 Bind connection locally to this port. See CURLOPT_LOCALPORT(3)
371 Bind connection locally to port range. See CURLOPT_LOCALPORTRANGE(3)
375 Timeout for DNS cache. See CURLOPT_DNS_CACHE_TIMEOUT(3)
380 See CURLOPT_DNS_USE_GLOBAL_CACHE(3)
384 Use this DoH server for name resolves. See CURLOPT_DOH_URL(3)
388 Ask for alternate buffer size. See CURLOPT_BUFFERSIZE(3)
392 Port number to connect to. See CURLOPT_PORT(3)
396 Enable TCP Fast Open. See CURLOPT_TCP_FASTOPEN(3)
400 Disable the Nagle algorithm. See CURLOPT_TCP_NODELAY(3)
404 IPv6 scope for local addresses. See CURLOPT_ADDRESS_SCOPE(3)
408 Enable TCP keep-alive. See CURLOPT_TCP_KEEPALIVE(3)
412 Idle time before sending keep-alive. See CURLOPT_TCP_KEEPIDLE(3)
416 Interval between keep-alive probes. See CURLOPT_TCP_KEEPINTVL(3)
420 Path to a Unix domain socket. See CURLOPT_UNIX_SOCKET_PATH(3)
424 Path to an abstract Unix domain socket. See CURLOPT_ABSTRACT_UNIX_SOCKET(3)
430 Enable .netrc parsing. See CURLOPT_NETRC(3)
434 .netrc filename. See CURLOPT_NETRC_FILE(3)
438 User name and password. See CURLOPT_USERPWD(3)
442 Proxy user name and password. See CURLOPT_PROXYUSERPWD(3)
446 User name. See CURLOPT_USERNAME(3)
450 Password. See CURLOPT_PASSWORD(3)
454 Login options. See CURLOPT_LOGIN_OPTIONS(3)
458 Proxy user name. See CURLOPT_PROXYUSERNAME(3)
462 Proxy password. See CURLOPT_PROXYPASSWORD(3)
466 HTTP server authentication methods. See CURLOPT_HTTPAUTH(3)
470 TLS authentication user name. See CURLOPT_TLSAUTH_USERNAME(3)
474 Proxy TLS authentication user name. See CURLOPT_PROXY_TLSAUTH_USERNAME(3)
478 TLS authentication password. See CURLOPT_TLSAUTH_PASSWORD(3)
482 Proxy TLS authentication password. See CURLOPT_PROXY_TLSAUTH_PASSWORD(3)
486 TLS authentication methods. See CURLOPT_TLSAUTH_TYPE(3)
490 Proxy TLS authentication methods. See CURLOPT_PROXY_TLSAUTH_TYPE(3)
494 HTTP proxy authentication methods. See CURLOPT_PROXYAUTH(3)
498 SASL authorization identity (identity to act as). See CURLOPT_SASL_AUTHZID(3)
502 Enable SASL initial response. See CURLOPT_SASL_IR(3)
506 OAuth2 bearer token. See CURLOPT_XOAUTH2_BEARER(3)
510 Do not allow username in URL. See CURLOPT_DISALLOW_USERNAME_IN_URL(3)
516 Automatically set Referer: header. See CURLOPT_AUTOREFERER(3)
520 Accept-Encoding and automatic decompressing data. See CURLOPT_ACCEPT_ENCODING(3)
524 Request Transfer-Encoding. See CURLOPT_TRANSFER_ENCODING(3)
528 Follow HTTP redirects. See CURLOPT_FOLLOWLOCATION(3)
536 Maximum number of redirects to follow. See CURLOPT_MAXREDIRS(3)
540 How to act on redirects after POST. See CURLOPT_POSTREDIR(3)
544 **Deprecated option** Issue an HTTP PUT request. See CURLOPT_PUT(3)
548 Issue an HTTP POST request. See CURLOPT_POST(3)
552 Send a POST with this data. See CURLOPT_POSTFIELDS(3)
556 The POST data is this big. See CURLOPT_POSTFIELDSIZE(3)
560 The POST data is this big. See CURLOPT_POSTFIELDSIZE_LARGE(3)
564 Send a POST with this data - and copy it. See CURLOPT_COPYPOSTFIELDS(3)
569 See CURLOPT_HTTPPOST(3)
573 Referer: header. See CURLOPT_REFERER(3)
577 User-Agent: header. See CURLOPT_USERAGENT(3)
581 Custom HTTP headers. See CURLOPT_HTTPHEADER(3)
585 Control custom headers. See CURLOPT_HEADEROPT(3)
589 Custom HTTP headers sent to proxy. See CURLOPT_PROXYHEADER(3)
593 Alternative versions of 200 OK. See CURLOPT_HTTP200ALIASES(3)
597 Cookie(s) to send. See CURLOPT_COOKIE(3)
601 File to read cookies from. See CURLOPT_COOKIEFILE(3)
605 File to write cookies to. See CURLOPT_COOKIEJAR(3)
609 Start a new cookie session. See CURLOPT_COOKIESESSION(3)
613 Add or control cookies. See CURLOPT_COOKIELIST(3)
617 Specify the Alt-Svc: cache filename. See CURLOPT_ALTSVC(3)
621 Enable and configure Alt-Svc: treatment. See CURLOPT_ALTSVC_CTRL(3)
625 Set HSTS cache file. See CURLOPT_HSTS(3)
629 Enable HSTS. See CURLOPT_HSTS_CTRL(3)
633 Set HSTS read callback. See CURLOPT_HSTSREADFUNCTION(3)
637 Pass pointer to the HSTS read callback. See CURLOPT_HSTSREADDATA(3)
641 Set HSTS write callback. See CURLOPT_HSTSWRITEFUNCTION(3)
645 Pass pointer to the HSTS write callback. See CURLOPT_HSTSWRITEDATA(3)
649 Do an HTTP GET request. See CURLOPT_HTTPGET(3)
665 Ignore Content-Length. See CURLOPT_IGNORE_CONTENT_LENGTH(3)
669 Disable Content decoding. See CURLOPT_HTTP_CONTENT_DECODING(3)
673 Disable Transfer decoding. See CURLOPT_HTTP_TRANSFER_DECODING(3)
677 100-continue timeout. See CURLOPT_EXPECT_100_TIMEOUT_MS(3)
681 Set callback for sending trailing headers. See
686 Custom pointer passed to the trailing headers callback. See
691 Wait on connection to pipeline on it. See CURLOPT_PIPEWAIT(3)
695 This HTTP/2 stream depends on another. See CURLOPT_STREAM_DEPENDS(3)
699 This HTTP/2 stream depends on another exclusively. See
704 Set this HTTP/2 stream's weight. See CURLOPT_STREAM_WEIGHT(3)
710 Address of the sender. See CURLOPT_MAIL_FROM(3)
714 Address of the recipients. See CURLOPT_MAIL_RCPT(3)
718 Authentication address. See CURLOPT_MAIL_AUTH(3)
722 Allow RCPT TO command to fail for some recipients. See
729 TFTP block size. See CURLOPT_TFTP_BLKSIZE(3)
733 Do not send TFTP options requests. See CURLOPT_TFTP_NO_OPTIONS(3)
739 Use active FTP. See CURLOPT_FTPPORT(3)
743 Commands to run before transfer. See CURLOPT_QUOTE(3)
747 Commands to run after transfer. See CURLOPT_POSTQUOTE(3)
751 Commands to run just before transfer. See CURLOPT_PREQUOTE(3)
755 Append to remote file. See CURLOPT_APPEND(3)
759 Use EPRT. See CURLOPT_FTP_USE_EPRT(3)
763 Use EPSV. See CURLOPT_FTP_USE_EPSV(3)
767 Use PRET. See CURLOPT_FTP_USE_PRET(3)
771 Create missing directories on the remote server. See CURLOPT_FTP_CREATE_MISSING_DIRS(3)
775 Timeout for server responses. See CURLOPT_SERVER_RESPONSE_TIMEOUT(3)
779 Timeout for server responses. See CURLOPT_SERVER_RESPONSE_TIMEOUT_MS(3)
783 Alternative to USER. See CURLOPT_FTP_ALTERNATIVE_TO_USER(3)
787 Ignore the IP address in the PASV response. See CURLOPT_FTP_SKIP_PASV_IP(3)
791 Control how to do TLS. See CURLOPT_FTPSSLAUTH(3)
795 Back to non-TLS again after authentication. See CURLOPT_FTP_SSL_CCC(3)
799 Send ACCT command. See CURLOPT_FTP_ACCOUNT(3)
803 Specify how to reach files. See CURLOPT_FTP_FILEMETHOD(3)
809 RTSP request. See CURLOPT_RTSP_REQUEST(3)
813 RTSP session-id. See CURLOPT_RTSP_SESSION_ID(3)
817 RTSP stream URI. See CURLOPT_RTSP_STREAM_URI(3)
821 RTSP Transport: header. See CURLOPT_RTSP_TRANSPORT(3)
825 Client CSEQ number. See CURLOPT_RTSP_CLIENT_CSEQ(3)
829 CSEQ number for RTSP Server->Client request. See CURLOPT_RTSP_SERVER_CSEQ(3)
833 AWS HTTP V4 Signature. See CURLOPT_AWS_SIGV4(3)
839 Use text transfer. See CURLOPT_TRANSFERTEXT(3)
843 Add transfer mode to URL over proxy. See CURLOPT_PROXY_TRANSFER_MODE(3)
847 Convert newlines. See CURLOPT_CRLF(3)
851 Range requests. See CURLOPT_RANGE(3)
855 Resume a transfer. See CURLOPT_RESUME_FROM(3)
859 Resume a transfer. See CURLOPT_RESUME_FROM_LARGE(3)
863 Set URL to work on with a URL handle. See CURLOPT_CURLU(3)
867 Custom request/method. See CURLOPT_CUSTOMREQUEST(3)
871 Request file modification date and time. See CURLOPT_FILETIME(3)
875 List only. See CURLOPT_DIRLISTONLY(3)
879 Do not get the body contents. See CURLOPT_NOBODY(3)
891 Upload data. See CURLOPT_UPLOAD(3)
895 Set upload buffer size. See CURLOPT_UPLOAD_BUFFERSIZE(3)
899 Post/send MIME data. See CURLOPT_MIMEPOST(3)
903 Set MIME option flags. See CURLOPT_MIME_OPTIONS(3)
907 Maximum file size to get. See CURLOPT_MAXFILESIZE(3)
911 Maximum file size to get. See CURLOPT_MAXFILESIZE_LARGE(3)
915 Make a time conditional request. See CURLOPT_TIMECONDITION(3)
919 Time value for the time conditional request. See CURLOPT_TIMEVALUE(3)
923 Time value for the time conditional request. See CURLOPT_TIMEVALUE_LARGE(3)
929 Timeout for the entire request. See CURLOPT_TIMEOUT(3)
933 Millisecond timeout for the entire request. See CURLOPT_TIMEOUT_MS(3)
937 Low speed limit to abort transfer. See CURLOPT_LOW_SPEED_LIMIT(3)
941 Time to be below the speed to trigger low speed abort. See CURLOPT_LOW_SPEED_TIME(3)
945 Cap the upload speed to this. See CURLOPT_MAX_SEND_SPEED_LARGE(3)
949 Cap the download speed to this. See CURLOPT_MAX_RECV_SPEED_LARGE(3)
953 Maximum number of connections in the connection pool. See CURLOPT_MAXCONNECTS(3)
961 Prevent subsequent connections from reusing this. See CURLOPT_FORBID_REUSE(3)
965 Limit the age (idle time) of connections for reuse. See CURLOPT_MAXAGE_CONN(3)
969 Limit the age (since creation) of connections for reuse. See
974 Timeout for the connection phase. See CURLOPT_CONNECTTIMEOUT(3)
978 Millisecond timeout for the connection phase. See CURLOPT_CONNECTTIMEOUT_MS(3)
982 IP version to use. See CURLOPT_IPRESOLVE(3)
986 Only connect, nothing else. See CURLOPT_CONNECT_ONLY(3)
990 Use TLS/SSL. See CURLOPT_USE_SSL(3)
994 Provide fixed/fake name resolves. See CURLOPT_RESOLVE(3)
998 Bind name resolves to this interface. See CURLOPT_DNS_INTERFACE(3)
1002 Bind name resolves to this IP4 address. See CURLOPT_DNS_LOCAL_IP4(3)
1006 Bind name resolves to this IP6 address. See CURLOPT_DNS_LOCAL_IP6(3)
1010 Preferred DNS servers. See CURLOPT_DNS_SERVERS(3)
1014 Shuffle addresses before use. See CURLOPT_DNS_SHUFFLE_ADDRESSES(3)
1018 Timeout for waiting for the server's connect back to be accepted. See
1023 Timeout for happy eyeballs. See CURLOPT_HAPPY_EYEBALLS_TIMEOUT_MS(3)
1027 Sets the interval at which connection upkeep are performed. See
1034 Client cert. See CURLOPT_SSLCERT(3)
1038 Client cert memory buffer. See CURLOPT_SSLCERT_BLOB(3)
1042 Proxy client cert. See CURLOPT_PROXY_SSLCERT(3)
1046 Proxy client cert memory buffer. See CURLOPT_PROXY_SSLCERT_BLOB(3)
1050 Client cert type. See CURLOPT_SSLCERTTYPE(3)
1054 Proxy client cert type. See CURLOPT_PROXY_SSLCERTTYPE(3)
1058 Client key. See CURLOPT_SSLKEY(3)
1062 Client key memory buffer. See CURLOPT_SSLKEY_BLOB(3)
1066 Proxy client key. See CURLOPT_PROXY_SSLKEY(3)
1070 Proxy client key. See CURLOPT_PROXY_SSLKEY_BLOB(3)
1074 Client key type. See CURLOPT_SSLKEYTYPE(3)
1078 Proxy client key type. See CURLOPT_PROXY_SSLKEYTYPE(3)
1082 Client key password. See CURLOPT_KEYPASSWD(3)
1086 Proxy client key password. See CURLOPT_PROXY_KEYPASSWD(3)
1090 Set key exchange curves. See CURLOPT_SSL_EC_CURVES(3)
1094 Enable use of ALPN. See CURLOPT_SSL_ENABLE_ALPN(3)
1098 **OBSOLETE** Enable use of NPN. See CURLOPT_SSL_ENABLE_NPN(3)
1102 Use identifier with SSL engine. See CURLOPT_SSLENGINE(3)
1106 Default SSL engine. See CURLOPT_SSLENGINE_DEFAULT(3)
1110 Enable TLS False Start. See CURLOPT_SSL_FALSESTART(3)
1114 SSL version to use. See CURLOPT_SSLVERSION(3)
1118 Proxy SSL version to use. See CURLOPT_PROXY_SSLVERSION(3)
1122 Verify the hostname in the SSL certificate. See CURLOPT_SSL_VERIFYHOST(3)
1126 Verify the hostname in the DoH (DNS-over-HTTPS) SSL certificate. See
1131 Verify the hostname in the proxy SSL certificate. See
1136 Verify the SSL certificate. See CURLOPT_SSL_VERIFYPEER(3)
1140 Verify the DoH (DNS-over-HTTPS) SSL certificate. See
1145 Verify the proxy SSL certificate. See CURLOPT_PROXY_SSL_VERIFYPEER(3)
1149 Verify the SSL certificate's status. See CURLOPT_SSL_VERIFYSTATUS(3)
1153 Verify the DoH (DNS-over-HTTPS) SSL certificate's status. See
1158 CA cert bundle. See CURLOPT_CAINFO(3)
1162 CA cert bundle memory buffer. See CURLOPT_CAINFO_BLOB(3)
1166 Proxy CA cert bundle. See CURLOPT_PROXY_CAINFO(3)
1170 Proxy CA cert bundle memory buffer. See CURLOPT_PROXY_CAINFO_BLOB(3)
1174 Issuer certificate. See CURLOPT_ISSUERCERT(3)
1178 Issuer certificate memory buffer. See CURLOPT_ISSUERCERT_BLOB(3)
1182 Proxy issuer certificate. See CURLOPT_PROXY_ISSUERCERT(3)
1186 Proxy issuer certificate memory buffer. See CURLOPT_PROXY_ISSUERCERT_BLOB(3)
1190 Path to CA cert bundle. See CURLOPT_CAPATH(3)
1194 Path to proxy CA cert bundle. See CURLOPT_PROXY_CAPATH(3)
1198 Certificate Revocation List. See CURLOPT_CRLFILE(3)
1202 Proxy Certificate Revocation List. See CURLOPT_PROXY_CRLFILE(3)
1206 Timeout for CA cache. See CURLOPT_CA_CACHE_TIMEOUT(3)
1210 Extract certificate info. See CURLOPT_CERTINFO(3)
1214 Set pinned SSL public key . See CURLOPT_PINNEDPUBLICKEY(3)
1218 Set the proxy's pinned SSL public key. See
1224 See CURLOPT_RANDOM_FILE(3)
1228 **OBSOLETE** Identify EGD socket for entropy. See CURLOPT_EGDSOCKET(3)
1232 Ciphers to use. See CURLOPT_SSL_CIPHER_LIST(3)
1236 Proxy ciphers to use. See CURLOPT_PROXY_SSL_CIPHER_LIST(3)
1240 TLS 1.3 cipher suites to use. See CURLOPT_TLS13_CIPHERS(3)
1244 Proxy TLS 1.3 cipher suites to use. See CURLOPT_PROXY_TLS13_CIPHERS(3)
1248 Disable SSL session-id cache. See CURLOPT_SSL_SESSIONID_CACHE(3)
1252 Control SSL behavior. See CURLOPT_SSL_OPTIONS(3)
1256 Control proxy SSL behavior. See CURLOPT_PROXY_SSL_OPTIONS(3)
1260 Kerberos security level. See CURLOPT_KRBLEVEL(3)
1264 Disable GSS-API delegation. See CURLOPT_GSSAPI_DELEGATION(3)
1270 SSH authentication types. See CURLOPT_SSH_AUTH_TYPES(3)
1274 Enable SSH compression. See CURLOPT_SSH_COMPRESSION(3)
1278 MD5 of host's public key. See CURLOPT_SSH_HOST_PUBLIC_KEY_MD5(3)
1282 SHA256 of host's public key. See CURLOPT_SSH_HOST_PUBLIC_KEY_SHA256(3)
1286 Filename of the public key. See CURLOPT_SSH_PUBLIC_KEYFILE(3)
1290 Filename of the private key. See CURLOPT_SSH_PRIVATE_KEYFILE(3)
1294 Filename with known hosts. See CURLOPT_SSH_KNOWNHOSTS(3)
1298 Callback for known hosts handling. See CURLOPT_SSH_KEYFUNCTION(3)
1302 Custom pointer to pass to ssh key callback. See CURLOPT_SSH_KEYDATA(3)
1306 Callback for checking host key handling. See CURLOPT_SSH_HOSTKEYFUNCTION(3)
1310 Custom pointer to pass to ssh host key callback. See CURLOPT_SSH_HOSTKEYDATA(3)
1316 Set WebSocket options. See CURLOPT_WS_OPTIONS(3)
1322 Private pointer to store. See CURLOPT_PRIVATE(3)
1326 Share object to use. See CURLOPT_SHARE(3)
1330 Mode for creating new remote files. See CURLOPT_NEW_FILE_PERMS(3)
1334 Mode for creating new remote directories. See CURLOPT_NEW_DIRECTORY_PERMS(3)
1339 about to call exit() anyway. See CURLOPT_QUICK_EXIT(3)
1345 TELNET options. See CURLOPT_TELNETOPTIONS(3)
1369 error occurred as *<curl/curl.h>* defines. See the libcurl-errors(3) man page