Section 3: library functions
CURLOPT_FTPSSLAUTH – set order in which to attempt TLS vs SSL when using FTP Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTPSSLAUTH, long order); DescriptionPass a long using one of the values from below, to alter how libcurl issues "AUTH TLS" or "AUTH SSL" when FTP over SSL is activated. This is only interesting if CURLOPT_USE_SSL(3) is…
CURLOPT_FTPPORT – make FTP transfer active Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTPPORT, char *spec); DescriptionPass a pointer to a zero terminated string as parameter. It specifies that the FTP transfer will be made actively and the given string will be used to get the IP address to use for the FTP PORT instruction. The PORT…
CURLOPT_FRESH_CONNECT – force a new connection to be used Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FRESH_CONNECT, long fresh); DescriptionPass a long. Set to 1 to make the next transfer use a new (fresh) connection by force instead of trying to re-use an existing one. This option should be used with caution and only if you understand…
CURLOPT_FORBID_REUSE – make connection get closed at once after use Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FORBID_REUSE, long close); DescriptionPass a long. Set close to 1 to make libcurl explicitly close the connection when done with the transfer. Normally, libcurl keeps all connections alive when done with one transfer in case a succeeding one follows that…
CURLOPT_FOLLOWLOCATION – follow HTTP 3xx redirects Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FOLLOWLOCATION, long enable); DescriptionA parameter set to 1 tells the library to follow any Location: header that the server sends as part of a HTTP header in a 3xx response. This means that libcurl will re-send the same request on the new location and…
CURLOPT_FNMATCH_FUNCTION – wildcard matching function callback Synopsis#include <curl/curl.h> int fnmatch_callback(void *ptr, const char *pattern, const char *string); CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FNMATCH_FUNCTION, fnmatch_callback);DescriptionPass a pointer to your callback function, which should match the prototype shown above. This callback s used for wildcard matching. Return CURL_FNMATCHFUNC_MATCH if pattern matches the string, CURL_FNMATCHFUNC_NOMATCH if not or CURL_FNMATCHFUNC_FAIL if…
CURLOPT_FNMATCH_DATA – custom pointer to fnmatch callback Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FNMATCH_DATA, void *pointer);DescriptionPass a pointer that will be untouched by libcurl and passed as the ptr argument to the CURL_FNMATCH_FUNCTION(3). DefaultNULL ProtocolsFTP ExampleTODO AvailabilityAdded in 7.21.0 Return ValueReturns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. See AlsoCURLOPT_FNMATCH_FUNCTION(3), CURLOPT_WILDCARDMATCH(3),
CURLOPT_FILETIME – get the modification time of the remote resource Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FILETIME, long gettime); DescriptionPass a long. If it is 1, libcurl will attempt to get the modification time of the remote document in this operation. This requires that the remote server sends the time or replies to a time querying…
CURLOPT_FAILONERROR – request failure on HTTP response >= 400 Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FAILONERROR, long fail); DescriptionA long parameter set to 1 tells the library to fail the request if the HTTP code returned is equal to or larger than 400. The default action would be to return the page normally, ignoring that code….
CURLOPT_EXPECT_100_TIMEOUT_MS – timeout for Expect: 100-continue response Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_EXPECT_100_TIMEOUT_MS, long milliseconds);DescriptionPass a long to tell libcurl the number of milliseconds to wait for a server response with the HTTP status 100 (Continue), 417 (Expectation Failed) or similar after sending a HTTP request containing an Expect: 100-continue header. If this times out…
CURLOPT_ERRORBUFFER – set error buffer for error messages Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_ERRORBUFFER, char *buf); DescriptionPass a char * to a buffer that the libcurl may store human readable error messages in on failures or problems. This may be more helpful than just the return code from curl_easy_perform(3) and related functions. The buffer must…
CURLOPT_EGDSOCKET – set EGD socket path Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_EGDSOCKET, char *path); DescriptionPass a char * to the zero terminated path name to the Entropy Gathering Daemon socket. It will be used to seed the random engine for SSL. DefaultNULL ProtocolsAll TLS based protocols: HTTPS, FTPS, IMAPS, POP3, SMTPS etc. ExampleTODO AvailabilityIf built…
CURLOPT_DNS_USE_GLOBAL_CACHE – enable/disable global DNS cache Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_USE_GLOBAL_CACHE, long enable); DescriptionPass a long. If the enable value is 1, it tells curl to use a global DNS cache that will survive between easy handle creations and deletions. This is not thread-safe and this will use a global variable. WARNING: this option…
CURLOPT_DNS_SERVERS – set preferred DNS servers Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_SERVERS, char *servers); DescriptionPass a char * that is the list of DNS servers to be used instead of the system default. The format of the dns servers option is: host[:port][,host[:port]]… For example: 192.168.1.100,192.168.1.101,3.4.5.6 DefaultNULL – use system default ProtocolsAll ExampleTODO AvailabilityThis option requires…
CURLOPT_DNS_LOCAL_IP6 – IPv6 address to bind DNS resolves to Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_LOCAL_IP6, char *address); DescriptionSet the local IPv6 address that the resolver should bind to. The argument should be of type char * and contain a single IPv6 address as a string. Set this option to NULL to use the default setting…
CURLOPT_DNS_LOCAL_IP4 – IPv4 address to bind DNS resolves to Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_LOCAL_IP4, char *address); DescriptionSet the local IPv4 address that the resolver should bind to. The argument should be of type char * and contain a single numerical IPv4 address as a string. Set this option to NULL to use the default…
CURLOPT_DNS_INTERFACE – set interface to speak DNS over Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_INTERFACE, char *ifname); DescriptionPass a char * as parameter. Set the name of the network interface that the DNS resolver should bind to. This must be an interface name (not an address). Set this option to NULL to use the default setting…
CURLOPT_DNS_CACHE_TIMEOUT – set life-time for DNS cache entries Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_CACHE_TIMEOUT, long age); DescriptionPass a long, this sets the timeout in seconds. Name resolves will be kept in memory and used for this number of seconds. Set to zero to completely disable caching, or set to -1 to make the cached entries…
CURLOPT_DIRLISTONLY – ask for names only in a directory listing Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DIRLISTONLY, long listonly); DescriptionFor FTP and SFTP based URLs a parameter set to 1 tells the library to list the names of files in a directory, rather than performing a full directory listing that would normally include file sizes, dates…
CURLOPT_DEBUGFUNCTION – debug callback Synopsis#include <curl/curl.h> typedef enum { CURLINFO_TEXT = 0, CURLINFO_HEADER_IN, /* 1 */ CURLINFO_HEADER_OUT, /* 2 */ CURLINFO_DATA_IN, /* 3 */ CURLINFO_DATA_OUT, /* 4 */ CURLINFO_SSL_DATA_IN, /* 5 */ CURLINFO_SSL_DATA_OUT, /* 6 */ CURLINFO_END } curl_infotype; int debug_callback(CURL *handle, curl_infotype type, char *data, size_t size, void *userptr); CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DEBUGFUNCTION, debug_callback);DescriptionPass…