93 lines
3.3 KiB
Groff
93 lines
3.3 KiB
Groff
|
.\" **************************************************************************
|
||
|
|
.\" * _ _ ____ _
|
||
|
|
.\" * Project ___| | | | _ \| |
|
||
|
|
.\" * / __| | | | |_) | |
|
||
|
|
.\" * | (__| |_| | _ <| |___
|
||
|
|
.\" * \___|\___/|_| \_\_____|
|
||
|
|
.\" *
|
||
|
|
.\" * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
|
||
|
|
.\" *
|
||
|
|
.\" * This software is licensed as described in the file COPYING, which
|
||
|
|
.\" * you should have received as part of this distribution. The terms
|
||
|
|
.\" * are also available at https://curl.haxx.se/docs/copyright.html.
|
||
|
|
.\" *
|
||
|
|
.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell
|
||
|
|
.\" * copies of the Software, and permit persons to whom the Software is
|
||
|
|
.\" * furnished to do so, under the terms of the COPYING file.
|
||
|
|
.\" *
|
||
|
|
.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
|
||
|
|
.\" * KIND, either express or implied.
|
||
|
|
.\" *
|
||
|
|
.\" **************************************************************************
|
||
|
|
.\"
|
||
|
|
.TH CURLOPT_IOCTLFUNCTION 3 "16 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options"
|
||
|
|
.SH NAME
|
||
|
|
CURLOPT_IOCTLFUNCTION \- callback for I/O operations
|
||
|
|
.SH SYNOPSIS
|
||
|
|
.nf
|
||
|
|
#include <curl/curl.h>
|
||
|
|
|
||
|
|
typedef enum {
|
||
|
|
CURLIOE_OK, /* I/O operation successful */
|
||
|
|
CURLIOE_UNKNOWNCMD, /* command was unknown to callback */
|
||
|
|
CURLIOE_FAILRESTART, /* failed to restart the read */
|
||
|
|
CURLIOE_LAST /* never use */
|
||
|
|
} curlioerr;
|
||
|
|
|
||
|
|
typedef enum {
|
||
|
|
CURLIOCMD_NOP, /* no operation */
|
||
|
|
CURLIOCMD_RESTARTREAD, /* restart the read stream from start */
|
||
|
|
CURLIOCMD_LAST /* never use */
|
||
|
|
} curliocmd;
|
||
|
|
|
||
|
|
curlioerr ioctl_callback(CURL *handle, int cmd, void *clientp);
|
||
|
|
|
||
|
|
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_IOCTLFUNCTION, ioctl_callback);
|
||
|
|
.SH DESCRIPTION
|
||
|
|
Pass a pointer to your callback function, which should match the prototype
|
||
|
|
shown above.
|
||
|
|
|
||
|
|
This callback function gets called by libcurl when something special
|
||
|
|
I/O-related needs to be done that the library can't do by itself. For now,
|
||
|
|
rewinding the read data stream is the only action it can request. The
|
||
|
|
rewinding of the read data stream may be necessary when doing an HTTP PUT or
|
||
|
|
POST with a multi-pass authentication method.
|
||
|
|
|
||
|
|
The callback MUST return \fICURLIOE_UNKNOWNCMD\fP if the input \fIcmd\fP is
|
||
|
|
not \fICURLIOCMD_RESTARTREAD\fP.
|
||
|
|
|
||
|
|
The \fIclientp\fP argument to the callback is set with the
|
||
|
|
\fICURLOPT_IOCTLDATA(3)\fP option.
|
||
|
|
|
||
|
|
This option is deprecated! Do not use it. Use \fICURLOPT_SEEKFUNCTION(3)\fP
|
||
|
|
instead to provide seeking! If \fICURLOPT_SEEKFUNCTION(3)\fP is set, this
|
||
|
|
parameter will be ignored when seeking.
|
||
|
|
.SH DEFAULT
|
||
|
|
By default, this parameter is set to NULL. Not used.
|
||
|
|
.SH PROTOCOLS
|
||
|
|
Used with HTTP
|
||
|
|
.SH EXAMPLE
|
||
|
|
.nf
|
||
|
|
static curlioerr ioctl_callback(CURL *handle, int cmd, void *clientp)
|
||
|
|
{
|
||
|
|
struct data *io = (struct data *)clientp;
|
||
|
|
if(cmd == CURLIOCMD_RESTARTREAD) {
|
||
|
|
lseek(fd, 0, SEEK_SET);
|
||
|
|
current_offset = 0;
|
||
|
|
return CURLIOE_OK;
|
||
|
|
}
|
||
|
|
return CURLIOE_UNKNOWNCMD;
|
||
|
|
}
|
||
|
|
{
|
||
|
|
struct data ioctl_data;
|
||
|
|
curl_easy_setopt(curl, CURLOPT_IOCTLFUNCTION, ioctl_callback);
|
||
|
|
curl_easy_setopt(curl, CURLOPT_IOCTLDATA, &ioctl_data);
|
||
|
|
}
|
||
|
|
.fi
|
||
|
|
.SH AVAILABILITY
|
||
|
|
Added in 7.12.3
|
||
|
|
.SH RETURN VALUE
|
||
|
|
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
|
||
|
|
.SH "SEE ALSO"
|
||
|
|
.BR CURLOPT_IOCTLDATA "(3), " CURLOPT_SEEKFUNCTION "(3), "
|