curl_ws_*.3: enhance

- all: SEE ALSO the libcurl-ws man page
- send: add example and return value information
- meta: mention that the returned data is read-only

Closes #11318

docs/libcurl/curl_ws_meta.3

@@ -109,11 +109,10 @@ static size_t writecb(unsigned char *buffer,
 .SH AVAILABILITY
 Added in 7.86.0.
 .SH RETURN VALUE
-This function returns a pointer to a \fIcurl_ws_frame\fP struct with
+This function returns a pointer to a \fIcurl_ws_frame\fP struct with read-only
 information that is valid for this specific callback invocation. If it cannot
 return this information, or if the function is called in the wrong context, it
 returns NULL.
 .SH "SEE ALSO"
-.BR curl_easy_setopt "(3), "
-.BR curl_easy_getinfo "(3), "
-.BR curl_ws_send "(3), " curl_ws_recv "(3), "
+.BR curl_easy_setopt "(3), " curl_easy_getinfo "(3), "
+.BR curl_ws_send "(3), " curl_ws_recv "(3), " libcurl-ws "(3), "

docs/libcurl/curl_ws_recv.3

@@ -66,4 +66,4 @@ this function again.
 .SH "SEE ALSO"
 .BR curl_easy_setopt "(3), " curl_easy_perform "(3), "
 .BR curl_easy_getinfo "(3), "
-.BR curl_ws_send "(3) "
+.BR curl_ws_send "(3), "  libcurl-ws "(3), "

docs/libcurl/curl_ws_send.3

@@ -80,13 +80,22 @@ expected fragment size in the first call and it needs to be zero in subsequent
 calls.
 .SH EXAMPLE
 .nf
-
+int ping(CURL *curl, const char *send_payload)
+{
+  size_t sent;
+  CURLcode result =
+    curl_ws_send(curl, send_payload, strlen(send_payload), &sent, 0,
+                 CURLWS_PING);
+  return (int)result;
+}
 .fi
 .SH AVAILABILITY
 Added in 7.86.0.
 .SH RETURN VALUE
-
+\fICURLE_OK\fP (zero) means that the data was sent properly, non-zero means an
+error occurred as \fI<curl/curl.h>\fP defines. See the \fIlibcurl-errors(3)\fP
+man page for the full list with descriptions.
 .SH "SEE ALSO"
 .BR curl_easy_setopt "(3), " curl_easy_perform "(3), "
 .BR curl_easy_getinfo "(3), "
-.BR curl_ws_recv "(3) "
+.BR curl_ws_recv "(3), " libcurl-ws "(3), "