docs(capi): output the hyper_version in the capi examples (#2623)

Author: seanmonstar

capi/examples/client.c

@@ -175,7 +175,7 @@ int main(int argc, char *argv[]) {
     hyper_io_set_read(io, read_cb);
     hyper_io_set_write(io, write_cb);
 
-    printf("http handshake ...\n");
+    printf("http handshake (hyper v%s) ...\n", hyper_version());
 
     // We need an executor generally to poll futures
     const hyper_executor *exec = hyper_executor_new();

capi/examples/upload.c

@@ -148,14 +148,13 @@ static int print_each_header(void *userdata,
     return HYPER_ITER_CONTINUE;
 }
 
-static void print_informational(void *userdata, hyper_response *resp) {
+static void print_informational(void *userdata, const hyper_response *resp) {
     uint16_t http_status = hyper_response_status(resp);
 
     printf("\nInformational (1xx): %d\n", http_status);
 
-    hyper_headers *headers = hyper_response_headers(resp);
-    hyper_headers_foreach(headers, print_each_header, NULL);
-    printf("\n");
+    const hyper_buf* headers = hyper_response_headers_raw(resp);
+    write(1, hyper_buf_bytes(headers), hyper_buf_len(headers));
 }
 
 typedef enum {
@@ -218,14 +217,15 @@ int main(int argc, char *argv[]) {
     hyper_io_set_read(io, read_cb);
     hyper_io_set_write(io, write_cb);
 
-    printf("http handshake ...\n");
+    printf("http handshake (hyper v%s) ...\n", hyper_version());
 
     // We need an executor generally to poll futures
     const hyper_executor *exec = hyper_executor_new();
 
     // Prepare client options
     hyper_clientconn_options *opts = hyper_clientconn_options_new();
     hyper_clientconn_options_exec(opts, exec);
+    hyper_clientconn_options_headers_raw(opts, 1);
 
     hyper_task *handshake = hyper_clientconn_handshake(io, opts);
     hyper_task_set_userdata(handshake, (void *)EXAMPLE_HANDSHAKE);
@@ -275,6 +275,10 @@ int main(int argc, char *argv[]) {
                 hyper_headers_set(req_headers, STR_ARG("host"), STR_ARG(host));
                 hyper_headers_set(req_headers, STR_ARG("expect"), STR_ARG("100-continue"));
 
+                // NOTE: We aren't handling *waiting* for the 100 Continue,
+                // the body is sent immediately. This will just print if any
+                // informational headers are received.
+                printf("    with expect-continue ...\n");
                 hyper_request_on_informational(req, print_informational, NULL);
 
                 // Prepare the req body