Linux Manuals session 3

CURLOPT_HEADERFUNCTION – callback that receives header data Synopsis#include <curl/curl.h> size_t header_callback(char *buffer,                  size_t size,                  size_t nitems,                  void *userdata); CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HEADERFUNCTION, header_callback); DescriptionPass a pointer to your callback function, which should match the prototype shown above. This function gets called by libcurl as soon as it has received header data. The header callback will be…

CURLOPT_HEADERDATA – pointer to pass to header callback Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HEADERDATA, void *pointer); DescriptionPass a pointer to be used to write the header part of the received data to. If CURLOPT_WRITEFUNCTION(3) or CURLOPT_HEADERFUNCTION(3) is used, pointer will be passed in to the respective callback. If neither of those options are set, pointer…

CURLOPT_HEADER – pass headers to the data stream Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HEADER, long onoff); DescriptionPass in onoff set to 1 to tell the library to include the header in the body output for requests with this handle. This option is relevant for protocols that actually have headers or other meta-data (like HTTP and…

CURLOPT_GSSAPI_DELEGATION – set allowed GSS-API delegation Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_GSSAPI_DELEGATION, long level); DescriptionSet the long parameter level to CURLGSSAPI_DELEGATION_FLAG to allow unconditional GSSAPI credential delegation. The delegation is disabled by default since 7.21.7. Set the parameter to CURLGSSAPI_DELEGATION_POLICY_FLAG to delegate only if the OK-AS-DELEGATE flag is set in the service ticket in case…

CURLOPT_FTP_USE_PRET – enable the PRET command Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTP_USE_PRET, long enable); DescriptionPass a long. If the value is 1, it tells curl to send a PRET command before PASV (and EPSV). Certain FTP servers, mainly drftpd, require this non-standard command for directory listings as well as up and downloads in PASV mode….

CURLOPT_FTP_USE_EPSV – enable/disable use of EPSV Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTP_USE_EPSV, long epsv); DescriptionPass epsv as a long. If the value is 1, it tells curl to use the EPSV command when doing passive FTP downloads (which it does by default). Using EPSV means that it will first attempt to use EPSV before using…

CURLOPT_FTP_USE_EPRT – enable/disable use of EPRT with FTP Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTP_USE_EPRT, long enabled); DescriptionPass a long. If the value is 1, it tells curl to use the EPRT command when doing active FTP downloads (which is enabled by CURLOPT_FTPPORT(3)). Using EPRT means that it will first attempt to use EPRT before using…

CURLOPT_FTP_SSL_CCC – switch off SSL again with FTP after auth Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTP_SSL_CCC,                     long how); DescriptionIf enabled, this option makes libcurl use CCC (Clear Command Channel). It shuts down the SSL/TLS layer after authenticating. The rest of the control channel communication will be unencrypted. This allows NAT routers to follow the FTP…

CURLOPT_FTP_SKIP_PASV_IP – ignore the IP address in the PASV response Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTP_SKIP_PASV_IP, long skip); DescriptionPass a long. If skip is set to 1, it instructs libcurl to not use the IP address the server suggests in its 227-response to libcurl’s PASV command when libcurl connects the data connection. Instead libcurl will…

CURLOPT_FTP_RESPONSE_TIMEOUT – time allowed to wait for FTP response Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTP_RESPONSE_TIMEOUT, long timeout); DescriptionPass a long. Causes libcurl to set a timeout period (in seconds) on the amount of time that the server is allowed to take in order to send a response message for a command before the session is…

CURLOPT_FTP_FILEMETHOD – select directory traversing method for FTP Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTP_FILEMETHOD, long method);DescriptionPass a long telling libcurl which method to use to reach a file on a FTP(S) server. This option exists because some server implementations aren’t compliant to what the standards say should work. The argument should be one of the…

CURLOPT_FTP_CREATE_MISSING_DIRS – create missing dirs for FTP and SFTP Synopsis#include <curl/curl.h> typedef enum { CURLFTP_CREATE_DIR_NONE, CURLFTP_CREATE_DIR, CURLFTP_CREATE_DIR_RETRY } curl_ftpcreatedir; CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTP_CREATE_MISSING_DIRS, long create);DescriptionPass a long telling libcurl to create the dir. If the value is CURLFTP_CREATE_DIR (1), libcurl will attempt to create any remote directory that it fails to "move" into. For FTP…

CURLOPT_FTP_ALTERNATIVE_TO_USER – command to use instead of USER with FTP Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTP_ALTERNATIVE_TO_USER, char *cmd);DescriptionPass a char * as parameter, pointing to a string which will be used to authenticate if the usual FTP "USER user" and "PASS password" negotiation fails. This is currently only known to be required when connecting to…

CURLOPT_FTP_ACCOUNT – set account info for FTP Synopsis#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FTP_ACCOUNT, char *account); DescriptionPass a pointer to a zero terminated string (or NULL to disable). When an FTP server asks for "account data" after user name and password has been provided, this data is sent off using the ACCT command. DefaultNULL ProtocolsFTP ExampleTODO…

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…