Index: src/shell.c.in
==================================================================
--- src/shell.c.in
+++ src/shell.c.in
@@ -1067,10 +1067,11 @@
 */
 #define SHELL_OPEN_UNSPEC     0      /* No open-mode specified */
 #define SHELL_OPEN_NORMAL     1      /* Normal database file */
 #define SHELL_OPEN_APPENDVFS  2      /* Use appendvfs */
 #define SHELL_OPEN_ZIPFILE    3      /* Use the zipfile virtual table */
+#define SHELL_OPEN_READONLY   4      /* Open a normal database read-only */
 
 /*
 ** These are the allowed shellFlgs values
 */
 #define SHFLG_Pagecache      0x00000001 /* The --pagecache option is used */
@@ -3256,10 +3257,11 @@
   ".once (-e|-x|FILE)     Output for the next SQL command only to FILE\n"
   "                         or invoke system text editor (-e) or spreadsheet (-x)\n"
   "                         on the output.\n"
   ".open ?OPTIONS? ?FILE? Close existing database and reopen FILE\n"
   "                         The --new option starts with an empty file\n"
+  "                         Other options: --readonly --append --zip\n"
   ".output ?FILE?         Send output to FILE or stdout\n"
   ".print STRING...       Print literal STRING\n"
   ".prompt MAIN CONTINUE  Replace the standard prompts\n"
   ".quit                  Exit this program\n"
   ".read FILENAME         Execute SQL in FILENAME\n"
@@ -3451,10 +3453,14 @@
         break;
       }
       case SHELL_OPEN_ZIPFILE: {
         sqlite3_open(":memory:", &p->db);
         break;
+      }
+      case SHELL_OPEN_READONLY: {
+        sqlite3_open_v2(p->zDbFilename, &p->db, SQLITE_OPEN_READONLY, 0);
+        break;
       }
       case SHELL_OPEN_UNSPEC:
       case SHELL_OPEN_NORMAL: {
         sqlite3_open(p->zDbFilename, &p->db);
         break;
@@ -6305,10 +6311,12 @@
       }else if( optionMatch(z, "zip") ){
         p->openMode = SHELL_OPEN_ZIPFILE;
 #endif
       }else if( optionMatch(z, "append") ){
         p->openMode = SHELL_OPEN_APPENDVFS;
+      }else if( optionMatch(z, "readonly") ){
+        p->openMode = SHELL_OPEN_READONLY;
       }else if( z[0]=='-' ){
         utf8_printf(stderr, "unknown option: %s\n", z);
         rc = 1;
         goto meta_command_exit;
       }
@@ -7983,10 +7991,11 @@
 #endif
   "   -newline SEP         set output row separator. Default: '\\n'\n"
   "   -nullvalue TEXT      set text string for NULL values. Default ''\n"
   "   -pagecache SIZE N    use N slots of SZ bytes each for page cache memory\n"
   "   -quote               set output mode to 'quote'\n"
+  "   -readonly            open the database read-only\n"
   "   -separator SEP       set output column separator. Default: '|'\n"
   "   -stats               print memory stats before each finalize\n"
   "   -version             show SQLite version\n"
   "   -vfs NAME            use NAME as the default VFS\n"
 #ifdef SQLITE_ENABLE_VFSTRACE
@@ -8232,10 +8241,12 @@
     }else if( strcmp(z,"-zip")==0 ){
       data.openMode = SHELL_OPEN_ZIPFILE;
 #endif
     }else if( strcmp(z,"-append")==0 ){
       data.openMode = SHELL_OPEN_APPENDVFS;
+    }else if( strcmp(z,"-readonly")==0 ){
+      data.openMode = SHELL_OPEN_READONLY;
     }
   }
   if( data.zDbFilename==0 ){
 #ifndef SQLITE_OMIT_MEMORYDB
     data.zDbFilename = ":memory:";