curlopt_seekfunction(3) [mojave man page]

CURLOPT_SEEKFUNCTION(3) 				     curl_easy_setopt options					   CURLOPT_SEEKFUNCTION(3)

NAME

       CURLOPT_SEEKFUNCTION - user callback for seeking in input stream

SYNOPSIS

       #include <curl/curl.h>

       /* These are the return codes for the seek callbacks */
       #define CURL_SEEKFUNC_OK       0
       #define CURL_SEEKFUNC_FAIL     1 /* fail the entire transfer */
       #define CURL_SEEKFUNC_CANTSEEK 2 /* tell libcurl seeking can't be done, so
					   libcurl might try other means instead */

       int seek_callback(void *userp, curl_off_t offset, int origin);

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SEEKFUNCTION, seek_callback);

DESCRIPTION

       Pass a pointer to your callback function, which should match the prototype shown above.

       This  function gets called by libcurl to seek to a certain position in the input stream and can be used to fast forward a file in a resumed
       upload (instead of reading all uploaded bytes with the normal read function/callback). It is also called to rewind a stream when  data  has
       already	been sent to the server and needs to be sent again. This may happen when doing a HTTP PUT or POST with a multi-pass authentication
       method, or when an existing HTTP connection is reused too late and the server closes the connection. The function shall work like  fseek(3)
       or lseek(3) and it gets SEEK_SET, SEEK_CUR or SEEK_END as argument for origin, although libcurl currently only passes SEEK_SET.

       userp is the pointer you set with CURLOPT_SEEKDATA(3).

       The  callback  function	must  return  CURL_SEEKFUNC_OK	on success, CURL_SEEKFUNC_FAIL to cause the upload operation to fail or CURL_SEEK-
       FUNC_CANTSEEK to indicate that while the seek failed, libcurl is free to work around the problem if possible. The latter can  sometimes	be
       done by instead reading from the input or similar.

       If  you	forward  the  input  arguments directly to fseek(3) or lseek(3), note that the data type for offset is not the same as defined for
       curl_off_t on many systems!

DEFAULT

       By default, this is NULL and unused.

PROTOCOLS

       HTTP, FTP, SFTP

EXAMPLE

       TODO

AVAILABILITY

       Added in 7.18.0

RETURN VALUE

       Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.

SEE ALSO

       CURLOPT_SEEKDATA(3), CURLOPT_IOCTLFUNCTION(3),

libcurl 7.54.0							 February 03, 2016					   CURLOPT_SEEKFUNCTION(3)

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CURLOPT_HTTP_VERSION(3) 				     curl_easy_setopt options					   CURLOPT_HTTP_VERSION(3)

NAME

       CURLOPT_HTTP_VERSION - specify HTTP protocol version to use

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HTTP_VERSION, long version);

DESCRIPTION

       Pass  version a long, set to one of the values described below. They ask libcurl to use the specific HTTP versions. This is not sensible to
       do unless you have a good reason. You have to set this option if you want to use libcurl's HTTP/2 support.

       Note that the HTTP version is just a request. libcurl will still prioritize to re-use an existing connection so it might then re-use a con-
       nection using a HTTP version you haven't asked for.

       CURL_HTTP_VERSION_NONE
	      We don't care about what version the library uses. libcurl will use whatever it thinks fit.

       CURL_HTTP_VERSION_1_0
	      Enforce HTTP 1.0 requests.

       CURL_HTTP_VERSION_1_1
	      Enforce HTTP 1.1 requests.

       CURL_HTTP_VERSION_2_0
	      Attempt HTTP 2 requests. libcurl will fall back to HTTP 1.1 if HTTP 2 can't be negotiated with the server. (Added in 7.33.0)

	      The alias CURL_HTTP_VERSION_2 was added in 7.43.0 to better reflect the actual protocol name.

       CURL_HTTP_VERSION_2TLS
	      Attempt  HTTP  2	over TLS (HTTPS) only. libcurl will fall back to HTTP 1.1 if HTTP 2 can't be negotiated with the HTTPS server. For
	      clear text HTTP servers, libcurl will use 1.1. (Added in 7.47.0)

       CURL_HTTP_VERSION_2_PRIOR_KNOWLEDGE
	      Issue non-TLS HTTP requests using HTTP/2 without HTTP/1.1 Upgrade. It requires prior  knowledge  that  the  server  supports  HTTP/2
	      straight away. HTTPS requests will still do HTTP/2 the standard way with negotiated protocol version in the TLS handshake. (Added in
	      7.49.0)

DEFAULT

       CURL_HTTP_VERSION_NONE

PROTOCOLS

       HTTP

EXAMPLE

       TODO

AVAILABILITY

       Along with HTTP

RETURN VALUE

       Returns CURLE_OK if HTTP is supported, and CURLE_UNKNOWN_OPTION if not.

SEE ALSO

       CURLOPT_SSLVERSION(3), CURLOPT_HTTP200ALIASES(3),

libcurl 7.54.0							   May 01, 2016 					   CURLOPT_HTTP_VERSION(3)

Linux and UNIX Man Pages

curlopt_seekfunction(3) [mojave man page]

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