curl/docs/libcurl/opts/CURLOPT_READDATA.3
Michael Kaufmann b676b66f4d docs: Improve the manual pages of some callbacks
- CURLOPT_HEADERFUNCTION: add newlines
- CURLOPT_INTERLEAVEFUNCTION: fix the description of 'userdata'
- CURLOPT_READDATA: mention crashes, same as in CURLOPT_WRITEDATA
- CURLOPT_READFUNCTION: rename 'instream' to 'userdata' and explain
  how to set it

Closes https://github.com/curl/curl/pull/2868
2018-08-11 14:33:28 -04:00

66 lines
2.5 KiB
Groff

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.TH CURLOPT_READDATA 3 "16 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options"
.SH NAME
CURLOPT_READDATA \- custom pointer passed to the read callback
.SH SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_READDATA, void *pointer);
.SH DESCRIPTION
Data \fIpointer\fP to pass to the file read function. If you use the
\fICURLOPT_READFUNCTION(3)\fP option, this is the pointer you'll get as
input in the 4th argument to the callback.
If you don't specify a read callback but instead rely on the default internal
read function, this data must be a valid readable FILE * (cast to 'void *').
If you're using libcurl as a win32 DLL, you \fBMUST\fP use a
\fICURLOPT_READFUNCTION(3)\fP if you set this option or you will experience
crashes.
.SH DEFAULT
By default, this is a FILE * to stdin.
.SH PROTOCOLS
This is used for all protocols when sending data.
.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
struct MyData this;
if(curl) {
curl_easy_setopt(curl, CURLOPT_URL, "http://example.com");
/* pass pointer that gets passed in to the
CURLOPT_READFUNCTION callback */
curl_easy_setopt(curl, CURLOPT_READDATA, &this);
curl_easy_perform(curl);
}
.fi
.SH AVAILABILITY
This option was once known by the older name CURLOPT_INFILE, the name
\fICURLOPT_READDATA(3)\fP was introduced in 7.9.7.
.SH RETURN VALUE
This will return CURLE_OK.
.SH "SEE ALSO"
.BR CURLOPT_READFUNCTION "(3), " CURLOPT_WRITEDATA "(3), "