--- lbbs/src/screen.c	2025/05/18 06:57:56	1.61
+++ lbbs/src/screen.c	2025/05/25 06:55:23	1.69
@@ -48,7 +48,7 @@ void moveto(int row, int col)
 
 void clrtoeol()
 {
-	prints("\033[K");
+	prints(CTRL_SEQ_CLR_LINE);
 }
 
 void clrline(int line_begin, int line_end)
@@ -58,7 +58,7 @@ void clrline(int line_begin, int line_en
 	for (i = line_begin; i <= line_end; i++)
 	{
 		moveto(i, 0);
-		prints("\033[K");
+		prints(CTRL_SEQ_CLR_LINE);
 	}
 }
 
@@ -241,7 +241,7 @@ int display_file_ex(const char *filename
 	long int percentile;
 	int loop;
 
-	if ((p_shm = get_file_shm(filename, &data_len, &line_total, &p_data, &p_line_offsets)) == NULL)
+	if ((p_shm = get_file_shm_readonly(filename, &data_len, &line_total, &p_data, &p_line_offsets)) == NULL)
 	{
 		log_error("get_file_shm(%s) error\n", filename);
 		return KEY_NULL;
@@ -293,7 +293,7 @@ int display_file_ex(const char *filename
 				input_ok = 1;
 				switch (ch)
 				{
-				// case KEY_NULL:
+				case KEY_NULL:
 				case KEY_TIMEOUT:
 					goto cleanup;
 				case KEY_HOME:
@@ -403,7 +403,8 @@ int display_file_ex(const char *filename
 		len = p_line_offsets[line_current + 1] - p_line_offsets[line_current];
 		if (len >= LINE_BUFFER_LEN)
 		{
-			log_error("Error length exceeds buffer size: %d\n", len);
+			log_error("buffer overflow: len=%ld(%ld - %ld) line=%ld \n",
+					  len, p_line_offsets[line_current + 1], p_line_offsets[line_current], line_current);
 			len = LINE_BUFFER_LEN - 1;
 		}
 
@@ -418,6 +419,11 @@ int display_file_ex(const char *filename
 	}
 
 cleanup:
+	if (detach_file_shm(p_shm) < 0)
+	{
+		log_error("detach_file_shm(%s) error\n", filename);
+	}
+
 	return ch;
 }
 
@@ -439,7 +445,7 @@ int show_top(const char *status)
 		status_f[len] = '\0';
 	}
 
-	len = split_line(BBS_current_section_name, 20, &truncate, &section_name_len);
+	len = split_line(BBS_current_section_name, BBS_section_name_max_len, &truncate, &section_name_len);
 	if (truncate)
 	{
 		log_error("Section name is truncated\n");
@@ -448,8 +454,7 @@ int show_top(const char *status)
 	moveto(1, 0);
 	clrtoeol();
 	prints("\033[1;44;33m%s\033[37m%*s%*s\033[33m 讨论区 [%s]\033[m",
-		   status_f, 32, BBS_name, 26, "", BBS_current_section_name);
-	iflush();
+		   status_f, 44 - status_len, BBS_name, 26 - section_name_len, "", BBS_current_section_name);
 
 	return 0;
 }
@@ -485,10 +490,9 @@ int show_bottom(const char *msg)
 	moveto(SCREEN_ROWS, 0);
 	clrtoeol();
 	prints("\033[1;44;33m[\033[36m%s\033[33m]%*s%*s帐号[\033[36m%s\033[33m]"
-		   "[\033[36m%1d\033[33m:\033[36m%2d\033[33m:\033[36m%2d\033[33m]\033[m",
-		   str_time, 21, msg_f, 13 - len_username, "", BBS_username,
+		   "[\033[36m%1d\033[33m天\033[36m%2d\033[33m时\033[36m%2d\033[33m分]\033[m",
+		   str_time, 21, msg_f, 9 - len_username, "", BBS_username,
 		   tm_online->tm_mday - 1, tm_online->tm_hour, tm_online->tm_min);
-	iflush();
 
 	return 0;
 }
@@ -502,26 +506,40 @@ int show_active_board()
 	static const void *p_data;
 	static const long *p_line_offsets;
 
+	static time_t t_last_show = 0;
+	static int line_last = 0;
+
 	char buffer[LINE_BUFFER_LEN];
 	long int len;
 
 	if (p_shm == NULL)
 	{
-		if ((p_shm = get_file_shm(DATA_ACTIVE_BOARD, &data_len, &line_total, &p_data, &p_line_offsets)) == NULL)
+		if ((p_shm = get_file_shm_readonly(DATA_ACTIVE_BOARD, &data_len, &line_total, &p_data, &p_line_offsets)) == NULL)
 		{
 			log_error("get_file_shm(%s) error\n", DATA_ACTIVE_BOARD);
 			return KEY_NULL;
 		}
 	}
 
-	clrline(3, 2 + ACTIVE_BOARD_HEIGHT);
+	if (time(0) - t_last_show >= 10)
+	{
+		line_last = line_current;
+		t_last_show = time(0);
+	}
+	else
+	{
+		line_current = line_last;
+	}
+
+	clrline(2, 2 + ACTIVE_BOARD_HEIGHT);
 
 	for (int i = 0; i < ACTIVE_BOARD_HEIGHT; i++)
 	{
 		len = p_line_offsets[line_current + 1] - p_line_offsets[line_current];
 		if (len >= LINE_BUFFER_LEN)
 		{
-			log_error("Error length exceeds buffer size: %d\n", len);
+			log_error("buffer overflow: len=%ld(%ld - %ld) line=%ld \n",
+					  len, p_line_offsets[line_current + 1], p_line_offsets[line_current], line_current);
 			len = LINE_BUFFER_LEN - 1;
 		}
 
@@ -538,7 +556,6 @@ int show_active_board()
 			break;
 		}
 	}
-	iflush();
 
 	return 0;
 }