curl/docs/libcurl/curl_ws_recv.3
Daniel Stenberg 734c1f8909
ws: if no connection is around, return error
- curl_ws_send returns CURLE_SEND_ERROR if data->conn is gone

- curl_ws_recv returns CURLE_GOT_NOTHING on connection close

- curl_ws_recv.3: mention new return code for connection close + example
  embryo

Closes #10084
2022-12-13 15:13:03 +01:00

66 lines
2.5 KiB
Groff

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.TH curl_ws_recv 3 "12 Jun 2022" "libcurl 7.85.0" "libcurl Manual"
.SH NAME
curl_ws_recv - receive WebSocket data
.SH SYNOPSIS
.nf
#include <curl/easy.h>
CURLcode curl_ws_recv(CURL *curl, void *buffer, size_t buflen,
size_t *recv, struct curl_ws_frame **meta);
.fi
.SH DESCRIPTION
This function call is EXPERIMENTAL.
Retrieves as much as possible of a received WebSocket data fragment into the
\fBbuffer\fP, but not more than \fBbuflen\fP bytes. \fIrecv\fP is set to the
number of bytes actually stored.
If there is more fragment data to deliver than what fits in the provided
\fIbuffer\fP, libcurl returns a full buffer and the application needs to call
this function again to continue draining the buffer.
The \fImeta\fP pointer gets set to point to a \fIstruct curl_ws_frame\fP that
contains information about the received data. See the \fIcurl_ws_meta(3)\fP
for details on that struct.
.SH EXAMPLE
.nf
size_t rlen;
struct curl_ws_frame *meta;
char buffer[256];
CURLcode result = curl_ws_recv(curl, buffer, sizeof(buffer), &rlen, &meta);
.fi
.SH AVAILABILITY
Added in 7.86.0.
.SH RETURN VALUE
Returns \fBCURLE_OK\fP if everything is okay, and a non-zero number for
errors. Returns \fBCURLE_GOT_NOTHING\fP if the associated connection is
closed.
.SH "SEE ALSO"
.BR curl_easy_setopt "(3), " curl_easy_perform "(3), "
.BR curl_easy_getinfo "(3), "
.BR curl_ws_send "(3) "