docs: fix C source code link in subscription

Closes [TD-18451](https://jira.taosdata.com:18080/browse/TD-18451)

docs/zh/07-develop/07-tmq.mdx

@@ -807,300 +807,9 @@ SHOW SUBSCRIPTIONS;
 以下是各语言的完整示例代码。
 
 <Tabs defaultValue="java" groupId="lang">
-<TabItem label="C" value="c">
-
-```c
-/*
- * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
- *
- * This program is free software: you can use, redistribute, and/or modify
- * it under the terms of the GNU Affero General Public License, version 3
- * or later ("AGPL"), as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-
-#include <assert.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <time.h>
-#include "taos.h"
-
-static int  running = 1;
-static char dbName[64] = "tmqdb";
-static char stbName[64] = "stb";
-static char topicName[64] = "topicname";
-
-static int32_t msg_process(TAOS_RES* msg) {
-  char    buf[1024];
-  int32_t rows = 0;
-
-  const char* topicName = tmq_get_topic_name(msg);
-  const char* dbName = tmq_get_db_name(msg);
-  int32_t     vgroupId = tmq_get_vgroup_id(msg);
-
-  printf("topic: %s\n", topicName);
-  printf("db: %s\n", dbName);
-  printf("vgroup id: %d\n", vgroupId);
-
-  while (1) {
-    TAOS_ROW row = taos_fetch_row(msg);
-    if (row == NULL) break;
-
-    TAOS_FIELD* fields = taos_fetch_fields(msg);
-    int32_t     numOfFields = taos_field_count(msg);
-    int32_t*    length = taos_fetch_lengths(msg);
-    int32_t     precision = taos_result_precision(msg);
-    const char* tbName = tmq_get_table_name(msg);
-    rows++;
-    taos_print_row(buf, row, fields, numOfFields);
-    printf("row content from %s: %s\n", (tbName != NULL ? tbName : "table null"), buf);
-  }
-
-  return rows;
-}
-
-static int32_t init_env() {
-  TAOS* pConn = taos_connect("localhost", "root", "taosdata", NULL, 0);
-  if (pConn == NULL) {
-    return -1;
-  }
-
-  TAOS_RES* pRes;
-  // drop database if exists
-  printf("create database\n");
-  pRes = taos_query(pConn, "drop database if exists tmqdb");
-  if (taos_errno(pRes) != 0) {
-    printf("error in drop tmqdb, reason:%s\n", taos_errstr(pRes));
-    return -1;
-  }
-  taos_free_result(pRes);
-
-  // create database
-  pRes = taos_query(pConn, "create database tmqdb");
-  if (taos_errno(pRes) != 0) {
-    printf("error in create tmqdb, reason:%s\n", taos_errstr(pRes));
-    return -1;
-  }
-  taos_free_result(pRes);
-
-  // create super table
-  printf("create super table\n");
-  pRes = taos_query(
-      pConn, "create table tmqdb.stb (ts timestamp, c1 int, c2 float, c3 varchar(16)) tags(t1 int, t3 varchar(16))");
-  if (taos_errno(pRes) != 0) {
-    printf("failed to create super table stb, reason:%s\n", taos_errstr(pRes));
-    return -1;
-  }
-  taos_free_result(pRes);
-
-  // create sub tables
-  printf("create sub tables\n");
-  pRes = taos_query(pConn, "create table tmqdb.ctb0 using tmqdb.stb tags(0, 'subtable0')");
-  if (taos_errno(pRes) != 0) {
-    printf("failed to create super table ctb0, reason:%s\n", taos_errstr(pRes));
-    return -1;
-  }
-  taos_free_result(pRes);
-
-  pRes = taos_query(pConn, "create table tmqdb.ctb1 using tmqdb.stb tags(1, 'subtable1')");
-  if (taos_errno(pRes) != 0) {
-    printf("failed to create super table ctb1, reason:%s\n", taos_errstr(pRes));
-    return -1;
-  }
-  taos_free_result(pRes);
-
-  pRes = taos_query(pConn, "create table tmqdb.ctb2 using tmqdb.stb tags(2, 'subtable2')");
-  if (taos_errno(pRes) != 0) {
-    printf("failed to create super table ctb2, reason:%s\n", taos_errstr(pRes));
-    return -1;
-  }
-  taos_free_result(pRes);
 
-  pRes = taos_query(pConn, "create table tmqdb.ctb3 using tmqdb.stb tags(3, 'subtable3')");
-  if (taos_errno(pRes) != 0) {
-    printf("failed to create super table ctb3, reason:%s\n", taos_errstr(pRes));
-    return -1;
-  }
-  taos_free_result(pRes);
-
-  // insert data
-  printf("insert data into sub tables\n");
-  pRes = taos_query(pConn, "insert into tmqdb.ctb0 values(now, 0, 0, 'a0')(now+1s, 0, 0, 'a00')");
-  if (taos_errno(pRes) != 0) {
-    printf("failed to insert into ctb0, reason:%s\n", taos_errstr(pRes));
-    return -1;
-  }
-  taos_free_result(pRes);
-
-  pRes = taos_query(pConn, "insert into tmqdb.ctb1 values(now, 1, 1, 'a1')(now+1s, 11, 11, 'a11')");
-  if (taos_errno(pRes) != 0) {
-    printf("failed to insert into ctb0, reason:%s\n", taos_errstr(pRes));
-    return -1;
-  }
-  taos_free_result(pRes);
-
-  pRes = taos_query(pConn, "insert into tmqdb.ctb2 values(now, 2, 2, 'a1')(now+1s, 22, 22, 'a22')");
-  if (taos_errno(pRes) != 0) {
-    printf("failed to insert into ctb0, reason:%s\n", taos_errstr(pRes));
-    return -1;
-  }
-  taos_free_result(pRes);
-
-  pRes = taos_query(pConn, "insert into tmqdb.ctb3 values(now, 3, 3, 'a1')(now+1s, 33, 33, 'a33')");
-  if (taos_errno(pRes) != 0) {
-    printf("failed to insert into ctb0, reason:%s\n", taos_errstr(pRes));
-    return -1;
-  }
-  taos_free_result(pRes);
-
-  taos_close(pConn);
-  return 0;
-}
-
-int32_t create_topic() {
-  printf("create topic\n");
-  TAOS_RES* pRes;
-  TAOS*     pConn = taos_connect("localhost", "root", "taosdata", NULL, 0);
-  if (pConn == NULL) {
-    return -1;
-  }
-
-  pRes = taos_query(pConn, "use tmqdb");
-  if (taos_errno(pRes) != 0) {
-    printf("error in use tmqdb, reason:%s\n", taos_errstr(pRes));
-    return -1;
-  }
-  taos_free_result(pRes);
-
-  pRes = taos_query(pConn, "create topic topicname as select ts, c1, c2, c3 from tmqdb.stb where c1 > 1");
-  if (taos_errno(pRes) != 0) {
-    printf("failed to create topic topicname, reason:%s\n", taos_errstr(pRes));
-    return -1;
-  }
-  taos_free_result(pRes);
-
-  taos_close(pConn);
-  return 0;
-}
-
-void tmq_commit_cb_print(tmq_t* tmq, int32_t code, void* param) {
-  printf("tmq_commit_cb_print() code: %d, tmq: %p, param: %p\n", code, tmq, param);
-}
-
-tmq_t* build_consumer() {
-  tmq_conf_res_t code;
-  tmq_conf_t*    conf = tmq_conf_new();
-  code = tmq_conf_set(conf, "enable.auto.commit", "true");
-  if (TMQ_CONF_OK != code) return NULL;
-  code = tmq_conf_set(conf, "auto.commit.interval.ms", "1000");
-  if (TMQ_CONF_OK != code) return NULL;
-  code = tmq_conf_set(conf, "group.id", "cgrpName");
-  if (TMQ_CONF_OK != code) return NULL;
-  code = tmq_conf_set(conf, "client.id", "user defined name");
-  if (TMQ_CONF_OK != code) return NULL;
-  code = tmq_conf_set(conf, "td.connect.user", "root");
-  if (TMQ_CONF_OK != code) return NULL;
-  code = tmq_conf_set(conf, "td.connect.pass", "taosdata");
-  if (TMQ_CONF_OK != code) return NULL;
-  code = tmq_conf_set(conf, "auto.offset.reset", "earliest");
-  if (TMQ_CONF_OK != code) return NULL;
-  code = tmq_conf_set(conf, "experimental.snapshot.enable", "true");
-  if (TMQ_CONF_OK != code) return NULL;
-  code = tmq_conf_set(conf, "msg.with.table.name", "true");
-  if (TMQ_CONF_OK != code) return NULL;
-
-  tmq_conf_set_auto_commit_cb(conf, tmq_commit_cb_print, NULL);
-
-  tmq_t* tmq = tmq_consumer_new(conf, NULL, 0);
-  tmq_conf_destroy(conf);
-  return tmq;
-}
-
-tmq_list_t* build_topic_list() {
-  tmq_list_t* topicList = tmq_list_new();
-  int32_t     code = tmq_list_append(topicList, "topicname");
-  if (code) {
-    return NULL;
-  }
-  return topicList;
-}
-
-void basic_consume_loop(tmq_t* tmq, tmq_list_t* topicList) {
-  int32_t code;
-
-  if ((code = tmq_subscribe(tmq, topicList))) {
-    fprintf(stderr, "%% Failed to tmq_subscribe(): %s\n", tmq_err2str(code));
-    return;
-  }
-
-  int32_t totalRows = 0;
-  int32_t msgCnt = 0;
-  int32_t timeout = 5000;
-  while (running) {
-    TAOS_RES* tmqmsg = tmq_consumer_poll(tmq, timeout);
-    if (tmqmsg) {
-      msgCnt++;
-      totalRows += msg_process(tmqmsg);
-      taos_free_result(tmqmsg);
-      /*} else {*/
-      /*break;*/
-    }
-  }
-
-  fprintf(stderr, "%d msg consumed, include %d rows\n", msgCnt, totalRows);
-}
-
-int main(int argc, char* argv[]) {
-  int32_t code;
-
-  if (init_env() < 0) {
-    return -1;
-  }
-
-  if (create_topic() < 0) {
-    return -1;
-  }
-
-  tmq_t* tmq = build_consumer();
-  if (NULL == tmq) {
-    fprintf(stderr, "%% build_consumer() fail!\n");
-    return -1;
-  }
-
-  tmq_list_t* topic_list = build_topic_list();
-  if (NULL == topic_list) {
-    return -1;
-  }
-
-  basic_consume_loop(tmq, topic_list);
-
-  code = tmq_unsubscribe(tmq);
-  if (code) {
-    fprintf(stderr, "%% Failed to unsubscribe: %s\n", tmq_err2str(code));
-  } else {
-    fprintf(stderr, "%% unsubscribe\n");
-  }
-
-  code = tmq_consumer_close(tmq);
-  if (code) {
-    fprintf(stderr, "%% Failed to close consumer: %s\n", tmq_err2str(code));
-  } else {
-    fprintf(stderr, "%% Consumer closed\n");
-  }
-
-  return 0;
-}
-
-```
-
-[查看源码](https://github.com/taosdata/TDengine/blob/develop/examples/c/tmq.c)
+<TabItem label="C" value="c">
+  <CDemo>
 </TabItem>
 
 <TabItem label="Java" value="java">

docs/zh/07-develop/_sub_c.mdx

 ```c
-{{#include docs/examples/c/subscribe_demo.c}}
-```
\ No newline at end of file
+{{#include docs/examples/c/tmq-example.c}}
+```