curl/docs/libcurl/opts/CURLOPT_IOCTLDATA.3
Daniel Stenberg 5b060a4108
docs: rewrite to present tense
... instead of using future tense.

+ numerous cleanups and improvements
+ stick to "reuse" not "re-use"
+ fewer contractions

Closes #11713
2023-08-23 23:26:10 +02:00

65 lines
2.2 KiB
Groff

.\" **************************************************************************
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.TH CURLOPT_IOCTLDATA 3 "16 Jun 2014" libcurl libcurl
.SH NAME
CURLOPT_IOCTLDATA \- pointer passed to I/O callback
.SH SYNOPSIS
.nf
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_IOCTLDATA, void *pointer);
.fi
.SH DESCRIPTION
Pass the \fIpointer\fP that is untouched by libcurl and passed as the 3rd
argument in the ioctl callback set with \fICURLOPT_IOCTLFUNCTION(3)\fP.
.SH DEFAULT
By default, the value of this parameter is NULL.
.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. Deprecated since 7.18.0.
.SH RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
.SH "SEE ALSO"
.BR CURLOPT_IOCTLFUNCTION "(3), " CURLOPT_SEEKFUNCTION "(3), "