SQLite

      rc = SQLITE_OK;
      break;
    case SQLITE_FCNTL_SIZE_HINT:
    case SQLITE_FCNTL_CHUNK_SIZE:
      /* no-op these */
      rc = SQLITE_OK;
      break;
    case SQLITE_FCNTL_PRAGMA: {
      char **aFcntl = (char**)pArg;
      if( aFcntl[1] && sqlite3_stricmp(aFcntl[1],"multiplex_truncate")==0 ){
        if( aFcntl[2] && aFcntl[2][0] ){
          if( sqlite3_stricmp(aFcntl[2], "on")==0
           || sqlite3_stricmp(aFcntl[2], "1")==0 ){
            pGroup->bTruncate = 1;
          }else
          if( sqlite3_stricmp(aFcntl[2], "off")==0
           || sqlite3_stricmp(aFcntl[2], "0")==0 ){
            pGroup->bTruncate = 0;
          }
        }
        aFcntl[0] = sqlite3_mprintf(pGroup->bTruncate ? "on" : "off");
        rc = SQLITE_OK;
        break;
      }
      /* If the multiplexor does not handle the pragma, pass it through
      ** into the default case. */
    }
    default:
      pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL, 0);
      if( pSubOpen ){
        rc = pSubOpen->pMethods->xFileControl(pSubOpen, op, pArg);
        if( op==SQLITE_FCNTL_VFSNAME && rc==SQLITE_OK ){
         *(char**)pArg = sqlite3_mprintf("multiplex/%z", *(char**)pArg);
        }

# 2014-09-25
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
#
# This file contains tests for the "truncate" option in the multiplexor.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set ::testprefix multiplex4

db close
sqlite3_shutdown
sqlite3_multiplex_initialize {} 0

# delete all filesl with the base name of $basename
#
proc multiplex_delete_db {basename} {
  foreach file [glob -nocomplain $basename.*] {
    forcedelete $file
  }
}

# Return a sorted list of all files with the base name of $basename.
# Except, delete all text from the end of $basename through the NNN
# suffix on the end of the filename.
#
proc multiplex_file_list {basename} {
  set x {}
  foreach file [glob -nocomplain $basename.*] {
    regsub "^$basename\\..*(\\d\\d\\d)\$" $file $basename.\\1 file
    lappend x $file
  }
  return [lsort $x]
}

do_test multiplex4-1.0 {
  multiplex_delete_db mx4test
  sqlite3 db {file:mx4test.db?chunksize=10&truncate=1} -uri 1 -vfs multiplex
  db eval {
    CREATE TABLE t1(x);
    INSERT INTO t1(x) VALUES(randomblob(250000));
  }
  multiplex_file_list mx4test
} {mx4test.001 mx4test.db}

do_test multiplex4-1.1 {
  db eval {
    DELETE FROM t1;
    VACUUM;
  }
  multiplex_file_list mx4test
} {mx4test.db}

do_test multiplex4-1.2 {
  db eval {PRAGMA multiplex_truncate}
} {on}
do_test multiplex4-1.3 {
  db eval {PRAGMA multiplex_truncate=off}
} {off}
do_test multiplex4-1.4 {
  db eval {PRAGMA multiplex_truncate}
} {off}
do_test multiplex4-1.5 {
  db eval {PRAGMA multiplex_truncate=on}
} {on}
do_test multiplex4-1.6 {
  db eval {PRAGMA multiplex_truncate}
} {on}
do_test multiplex4-1.7 {
  db eval {PRAGMA multiplex_truncate=0}
} {off}
do_test multiplex4-1.8 {
  db eval {PRAGMA multiplex_truncate=1}
} {on}
do_test multiplex4-1.9 {
  db eval {PRAGMA multiplex_truncate=0}
} {off}

do_test multiplex4-1.10 {
  db eval {
    INSERT INTO t1(x) VALUES(randomblob(250000));
  }
  multiplex_file_list mx4test
} {mx4test.001 mx4test.db}

do_test multiplex4-1.11 {
  db eval {
    DELETE FROM t1;
    VACUUM;
  }
  multiplex_file_list mx4test
} {mx4test.001 mx4test.db}

do_test multiplex4-1.12 {
  db eval {
    PRAGMA multiplex_truncate=ON;
    DROP TABLE t1;
    VACUUM;
  }
  multiplex_file_list mx4test
} {mx4test.db}

catch { db close }
forcedelete mx4test.db
sqlite3_multiplex_shutdown
finish_test