diff --git a/ChangeLog b/ChangeLog
index 4d37d63..ac4db4b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,6 @@
+2024-05-26 Konstantin Kushnir <chpock@gmail.com>
+	* Add tests for writer
+
 2024-05-25 Konstantin Kushnir <chpock@gmail.com>
 	* Add support for writer in C
 
diff --git a/generic/vfsDriver.c b/generic/vfsDriver.c
index fa07e6c..dc52f8b 100644
--- a/generic/vfsDriver.c
+++ b/generic/vfsDriver.c
@@ -823,6 +823,12 @@ static int CookfsDeleteFile(Tcl_Obj *pathPtr) {
         return TCL_ERROR;
     }
 
+    if (Cookfs_FsindexEntryIsPending(entry)) {
+        CookfsLog(printf("CookfsDeleteFile: the entry is pending,"
+            " remove it from small file buffer"));
+        Cookfs_WriterRemoveFile(vfs->writer, entry);
+    }
+
     int result = Cookfs_FsindexUnset(index, internalRep->relativePathObj);
 
     // Check to see if anything's wrong
diff --git a/generic/writer.c b/generic/writer.c
index 5ed76b8..d2a764f 100644
--- a/generic/writer.c
+++ b/generic/writer.c
@@ -178,7 +178,7 @@ int Cookfs_WriterAddBufferToSmallFiles(Cookfs_Writer *w, Tcl_Obj *pathObj,
     if (wb->entry == NULL) {
         CookfsLog(printf("Cookfs_WriterAddBufferToSmallFiles: failed to create"
             " the entry"));
-        Cookfs_WriterSetLastError(w, "unable to create entry");
+        Cookfs_WriterSetLastError(w, "Unable to create entry");
         Cookfs_WriterWriterBufferFree(wb);
         return TCL_ERROR;
     }
@@ -241,6 +241,43 @@ static Tcl_WideInt Cookfs_WriterReadChannel(char *buffer,
 
 }
 
+int Cookfs_WriterRemoveFile(Cookfs_Writer *w, Cookfs_FsindexEntry *entry) {
+    CookfsLog(printf("Cookfs_WriterRemoveFile: enter"));
+    Cookfs_WriterBuffer *wbPrev = NULL;
+    Cookfs_WriterBuffer *wb = w->bufferFirst;
+    while (wb != NULL) {
+        if (wb->entry == entry) {
+
+            CookfsLog(printf("Cookfs_WriterRemoveFile: found the buffer"
+                " to remove [%p]", (void *)wb));
+            Cookfs_WriterBuffer *next = wb->next;
+            if (wbPrev == NULL) {
+                w->bufferFirst = next;
+            } else {
+                wbPrev->next = next;
+            }
+            w->bufferCount--;
+            w->bufferSize -= wb->bufferSize;
+            Cookfs_WriterWriterBufferFree(wb);
+
+            // Shift block number for the following files and their entries
+            while (next != NULL) {
+                CookfsLog(printf("Cookfs_WriterRemoveFile: shift buffer number"
+                    " for buffer [%p]", (void *)next));
+                next->entry->data.fileInfo.fileBlockOffsetSize[0]++;
+                next = next->next;
+            }
+
+            return 1;
+        }
+        wbPrev = wb;
+        wb = wb->next;
+    }
+    CookfsLog(printf("Cookfs_WriterRemoveFile: could not find the buffer"
+        " to remove"));
+    return 0;
+}
+
 #define DATA_FILE    (Tcl_Obj *)data
 #define DATA_CHANNEL (Tcl_Channel)data
 #define DATA_OBJECT  (Tcl_Obj *)data
@@ -269,6 +306,24 @@ int Cookfs_WriterAddFile(Cookfs_Writer *w, Tcl_Obj *pathObj,
     Tcl_DString chanTranslation, chanEncoding;
     Cookfs_FsindexEntry *entry = NULL;
 
+    // Check if we have the file in the small file buffer. We will try to get
+    // the fsindex entry for this file and see if it is a pending file.
+    entry = Cookfs_FsindexGet(w->index, pathObj);
+    if (entry != NULL) {
+        CookfsLog(printf("Cookfs_WriterAddFile: an existing entry for the file"
+            " was found"));
+        if (Cookfs_FsindexEntryIsPending(entry)) {
+            CookfsLog(printf("Cookfs_WriterAddFile: the entry is pending,"
+                " remove it from small file buffer"));
+            Cookfs_WriterRemoveFile(w, entry);
+        } else {
+            CookfsLog(printf("Cookfs_WriterAddFile: the entry is"
+                " not pending"));
+        }
+        entry = NULL;
+    }
+
+
     switch (dataType) {
 
     case COOKFS_WRITER_SOURCE_BUFFER:
@@ -349,7 +404,7 @@ int Cookfs_WriterAddFile(Cookfs_Writer *w, Tcl_Obj *pathObj,
     case COOKFS_WRITER_SOURCE_OBJECT: ; // an empty statement
 
         int length;
-        data = (void *)Tcl_GetStringFromObj(DATA_OBJECT, &length);
+        data = (void *)Tcl_GetByteArrayFromObj(DATA_OBJECT, &length);
 
         if (dataSize < 0) {
             CookfsLog(printf("Cookfs_WriterAddFile: get datasize from"
@@ -386,7 +441,7 @@ int Cookfs_WriterAddFile(Cookfs_Writer *w, Tcl_Obj *pathObj,
         if (entry == NULL) {
             CookfsLog(printf("Cookfs_WriterAddFile: failed to create"
                 " the entry"));
-            Cookfs_WriterSetLastError(w, "unable to create entry");
+            Cookfs_WriterSetLastError(w, "Unable to create entry");
             goto error;
         }
         // Set entry block information
@@ -474,7 +529,10 @@ int Cookfs_WriterAddFile(Cookfs_Writer *w, Tcl_Obj *pathObj,
         }
 
         // Calculate number of blocks
-        int numBlocks = (dataSize / w->pageSize) + 1;
+        int numBlocks = dataSize / w->pageSize;
+        if (dataSize % w->pageSize) {
+            numBlocks++;
+        }
 
         // Create an entry
         CookfsLog(printf("Cookfs_WriterAddFile: create an entry"
@@ -483,7 +541,7 @@ int Cookfs_WriterAddFile(Cookfs_Writer *w, Tcl_Obj *pathObj,
         if (entry == NULL) {
             CookfsLog(printf("Cookfs_WriterAddFile: failed to create"
                 " the entry"));
-            Cookfs_WriterSetLastError(w, "unable to create entry");
+            Cookfs_WriterSetLastError(w, "Unable to create entry");
             goto error;
         }
         Cookfs_FsindexUpdateEntryFileSize(entry, dataSize);
@@ -640,7 +698,8 @@ int Cookfs_WriterPurge(Cookfs_Writer *w) {
     // To solve this problem, we will check the buffers and if they are
     // identical, then we will use the same sort key for those buffers.
 
-    CookfsLog(printf("Cookfs_WriterPurge: sort %d entries", w->bufferCount));
+    CookfsLog(printf("Cookfs_WriterPurge: have total %d entries",
+        w->bufferCount));
     // Create array for all our entries
     sortedWB = ckalloc(w->bufferCount * sizeof(Cookfs_WriterBuffer *));
     if (sortedWB == NULL) {
diff --git a/generic/writer.h b/generic/writer.h
index 154c92f..3438104 100644
--- a/generic/writer.h
+++ b/generic/writer.h
@@ -72,6 +72,8 @@ const void *Cookfs_WriterGetBuffer(Cookfs_Writer *w, int blockNumber,
 int Cookfs_WriterAddFile(Cookfs_Writer *w, Tcl_Obj *pathObj,
     Cookfs_WriterDataSource dataType, void *data, Tcl_WideInt dataSize);
 
+int Cookfs_WriterRemoveFile(Cookfs_Writer *w, Cookfs_FsindexEntry *entry);
+
 int Cookfs_WriterGetWritetomemory(Cookfs_Writer *w);
 void Cookfs_WriterSetWritetomemory(Cookfs_Writer *w, int status);
 
diff --git a/scripts/vfs.tcl b/scripts/vfs.tcl
index 6b6e372..c61d05d 100644
--- a/scripts/vfs.tcl
+++ b/scripts/vfs.tcl
@@ -689,7 +689,9 @@ proc cookfs::tcl::vfs::delete {fsid root relative actualpath type recursive} {
         }  else  {
             vfs::filesystem posixerror $::cookfs::posix(ENOTDIR)
         }
-    }  elseif {$type == "directory" && $recursive} {
+    } elseif {$type eq "file"} {
+        $fs(writer) deleteFile $relative
+    } elseif {$type == "directory" && $recursive} {
         if {[catch {
             foreach ch [$fs(index) list $relative] {
                 # check type and delete appropriately
diff --git a/scripts/writer.tcl b/scripts/writer.tcl
index 80ca137..c7da70f 100644
--- a/scripts/writer.tcl
+++ b/scripts/writer.tcl
@@ -92,6 +92,9 @@ proc cookfs::tcl::writer::handle { name cmd args } {
         write {
             tailcall write $name {*}$args
         }
+        deleteFile {
+            tailcall deleteFile $name {*}$args
+        }
         writetomemory {
             if { [llength $args] > 1 } {
                 error "wrong # args: should be \"$name\
@@ -210,12 +213,46 @@ proc cookfs::tcl::writer::purge {wrid} {
     }
 }
 
+proc cookfs::tcl::writer::deleteFile {wrid args} {
+    upvar #0 $wrid c
+    # args - path type data size
+    foreach path_to_delete $args {
+        set idx 0
+        set deleted 0
+        set newsmallfilepaths [list]
+        foreach { path size clk } $c(smallfilepaths) {
+            if { !$deleted } {
+                if { $path eq $path_to_delete } {
+                    set c(smallfilebuf) [lreplace $c(smallfilebuf) $idx $idx]
+                    set c(smallfilebufsize) [expr { $c(smallfilebufsize) - $size }]
+                    set deleted 1
+                } else {
+                    lappend newsmallfilepaths $path $size $clk
+                    incr idx
+                }
+            } else {
+                # shift buffer number for other files
+                set entry [$c(index) get $path]
+                set chunklist [lindex $entry 2]
+                set chunklist [lreplace $chunklist 0 0 [expr { [lindex $chunklist 0] + 1 }]]
+                $c(index) set $path [lindex $entry 0] $chunklist
+                set entry [$c(index) get $path]
+                lappend newsmallfilepaths $path $size $clk
+            }
+        }
+        if { $deleted } {
+            set c(smallfilepaths) $newsmallfilepaths
+        }
+    }
+}
+
 proc cookfs::tcl::writer::write {wrid args} {
     upvar #0 $wrid c
     # args - path type data size
 
     # iterate over arguments
     foreach {path datatype data size} $args {
+        deleteFile $wrid $path
         if {$size == ""} {
             # read actual size, from file or channel
             switch -- $datatype {
@@ -249,6 +286,8 @@ proc cookfs::tcl::writer::write {wrid args} {
             channel {
                 set clk [clock seconds]
                 set chan $data
+                set translation [fconfigure $chan -translation]
+                set encoding [fconfigure $chan -encoding]
                 fconfigure $chan -translation binary
                 set doclose 0
                 set rawdata 0
@@ -274,12 +313,22 @@ proc cookfs::tcl::writer::write {wrid args} {
             }
 
             set sfidx [llength $c(smallfilebuf)]
+
+            if { [catch {
+                $c(index) set $path $clk [list [expr {-$sfidx - 1}] 0 $size]
+            } res opts] } {
+                if { $doclose } {
+                    close $chan
+                } elseif { $datatype eq "channel" } {
+                    fconfigure $chan -translation $translation -encoding $encoding
+                }
+                return -options $opts "unable to add \"$path\": $res"
+            }
+
             lappend c(smallfilebuf) $fc
             lappend c(smallfilepaths) $path $size $clk
             incr c(smallfilebufsize) [string length $fc]
 
-            $c(index) set $path $clk [list [expr {-$sfidx - 1}] 0 $size]
-
             # if current buffer exceeds maximum, write small files to clean it
             # but only if not writing to memory
             if {(!$c(writetomemory)) && ($c(smallfilebufsize) >= $c(smallfilebuffersize))} {
@@ -316,7 +365,11 @@ proc cookfs::tcl::writer::write {wrid args} {
 
             $c(index) set $path $clk $chunklist
         }
-        if {$doclose} {close $chan}
+        if { $doclose } {
+            close $chan
+        } elseif { $datatype eq "channel" } {
+            fconfigure $chan -translation $translation -encoding $encoding
+        }
     }
 }
 
diff --git a/tests/all.tcl b/tests/all.tcl
index 01e5cd7..6420903 100644
--- a/tests/all.tcl
+++ b/tests/all.tcl
@@ -1,4 +1,4 @@
-package require tcltest
+source [file join [file dirname [info script]] tcltestex.tcl]
 
 #lappend auto_path [pwd]
 
diff --git a/tests/dedup.test b/tests/dedup.test
index 82cc7ee..45405da 100644
--- a/tests/dedup.test
+++ b/tests/dedup.test
@@ -40,3 +40,107 @@ tcltest::test cookfsDedup-1.2 "Small file deduplication for same resulting pages
     tcltest::removeFile $file
 } -result 1
 
+tcltest::test cookfsDedup-1.3 "Small file deduplication for different resulting pages" -setup {
+    set file [tcltest::makeFile {} pages.cfs]
+} -body {
+    set datas [randomDatas 4 2048]
+    set c [vfs::cookfs::Mount $file $file -compression none \
+        -pagesize 4096 -smallfilesize 4096 -smallfilebuffer 16384]
+    # datas is 4 files of 2048 bytes each
+    # page has 4096 bytes
+    # file1 contains datas#0 comes to page#0[0]
+    # file2 contains datas#1 comes to page#0[1] - flush page now
+    # file3 contains datas#2 comes to page#1[0]
+    # file4 contains datas#0 uses page#0[0]
+    # file5 contains datas#3 comes to page#1[1] - flush page now
+    set files [list \
+        file1 [lindex $datas 0] \
+        file2 [lindex $datas 1] \
+        file3 [lindex $datas 2] \
+        file4 [lindex $datas 0] \
+        file5 [lindex $datas 3] \
+    ]
+    foreach { f d } $files {
+        set fh [open $file/$f w]
+        fconfigure $fh -translation binary
+        puts -nonewline $fh $d
+        close $fh
+    }
+    vfs::unmount $file
+    set fs [file size $file]
+    set result [list]
+    # the file size should be (2 pages + internal data) and less than (3 pages)
+    lappend result [expr {($fs > (4096 * 2)) && ($fs < (4096 * 3))}]
+    set c [vfs::cookfs::Mount -readonly $file $file]
+    foreach { f d } $files {
+        lappend result "$f [[$c getindex] get $f] [string equal $d [read [set fh [open $file/$f rb]]][close $fh]]"
+    }
+    join $result \n
+} -cleanup {
+    catch {vfs::unmount $file}
+    tcltest::removeFile $file
+} -match glob -result {1
+file1 * 2048 {0 0 2048} 1
+file2 * 2048 {0 2048 2048} 1
+file3 * 2048 {1 0 2048} 1
+file4 * 2048 {0 0 2048} 1
+file5 * 2048 {1 2048 2048} 1}
+
+tcltest::test cookfsDedup-1.4 "Small file deduplication for different resulting pages" -setup {
+    set file [tcltest::makeFile {} pages.cfs]
+} -body {
+    set datas [randomDatas 3 2048]
+    set c [vfs::cookfs::Mount $file $file -compression none \
+        -pagesize 4096 -smallfilesize 4096 -smallfilebuffer 8192]
+    # datas is 3 files of 2048 bytes each
+    # page has 4096 bytes
+    # file1 contains datas#0 comes to page#0[0]
+    # file2 contains datas#1 comes to page#0[1] - flush page now
+    # file3 contains datas#1 uses page#0[1]
+    # file4 contains datas#1 uses page#0[1] - the buffer size of the small file
+    #                                          has reached the limit and should be flushed.
+    #                                          But only 1 page should be used for all 4 files.
+    # file5 contains datas#0
+    # file6 contains datas#1 - flush page now, but it appears the same page as #0,
+    #                           so no new pages need to be created.
+    # file7 contains data#1 uses page#0[1]
+    # file8 contains data#2 uses page#1[0] - unmount now and flush page#1, even if it's not filled
+    set files [list \
+        file1 [lindex $datas 0] \
+        file2 [lindex $datas 1] \
+        file3 [lindex $datas 1] \
+        file4 [lindex $datas 1] \
+        file5 [lindex $datas 0] \
+        file6 [lindex $datas 1] \
+        file7 [lindex $datas 1] \
+        file8 [lindex $datas 2] \
+    ]
+    foreach { f d } $files {
+        set fh [open $file/$f w]
+        fconfigure $fh -translation binary
+        puts -nonewline $fh $d
+        close $fh
+    }
+    vfs::unmount $file
+    set fs [file size $file]
+    set result [list]
+    # the file size should be (1.5 pages + internal data) and less than (2 pages)
+    lappend result [expr {($fs > (1.5 * 4096)) && ($fs < (4096 * 2))}]
+    set c [vfs::cookfs::Mount -readonly $file $file]
+    foreach { f d } $files {
+        lappend result "$f [[$c getindex] get $f] [string equal $d [read [set fh [open $file/$f rb]]][close $fh]]"
+    }
+    join $result \n
+} -cleanup {
+    catch {vfs::unmount $file}
+    tcltest::removeFile $file
+} -match glob -result {1
+file1 * 2048 {0 0 2048} 1
+file2 * 2048 {0 2048 2048} 1
+file3 * 2048 {0 2048 2048} 1
+file4 * 2048 {0 2048 2048} 1
+file5 * 2048 {0 0 2048} 1
+file6 * 2048 {0 2048 2048} 1
+file7 * 2048 {0 2048 2048} 1
+file8 * 2048 {1 0 2048} 1}
+
diff --git a/tests/tcltestex.tcl b/tests/tcltestex.tcl
new file mode 100644
index 0000000..45f6427
--- /dev/null
+++ b/tests/tcltestex.tcl
@@ -0,0 +1,33 @@
+# (c) 2024 Konstantin Kushnir
+
+package require tcltest
+
+namespace eval tcltest {
+    namespace export makeBinFile viewBinFile
+}
+
+proc tcltest::makeBinFile { data args } {
+    if { [catch [list uplevel #0 [list tcltest::makeFile {} {*}$args]] res opts] } {
+        return -options $opts $res
+    }
+    set fp [open $res wb]
+    if { [string length $data] } {
+        puts -nonewline $fp $data
+    }
+    close $fp
+    return $res
+}
+
+proc tcltest::viewBinFile { name args } {
+    FillFilesExisted
+    if { [llength $args] } {
+        set dir [lindex $args 0]
+    } else {
+        set dir [temporaryDirectory]
+    }
+    set name [file join $dir $name]
+    set fp [open $name rb]
+    set data [read $fp]
+    close $fp
+    return $data
+}
\ No newline at end of file
diff --git a/tests/writer.test b/tests/writer.test
new file mode 100644
index 0000000..942e1d1
--- /dev/null
+++ b/tests/writer.test
@@ -0,0 +1,322 @@
+
+tcltest::test cookfsWriter-1.1 "Add small files" -setup {
+    set vfs [tcltest::makeFile {} pages.cfs]
+} -body {
+    set datas [randomDatas 3 1024]
+    set file1 [tcltest::makeBinFile [lindex $datas 0] file1]
+    set file2 [tcltest::makeBinFile [lindex $datas 1] file2]
+    set h [vfs::cookfs::Mount $vfs $vfs -pagesize 4096 -smallfilesize 4096 -smallfilebuffer 16384 -compression none]
+    set channel [open $file1 rb]
+    $h writeFiles file1 channel $channel "" file2 file $file2 "" file3 data [lindex $datas 2] ""
+    close $channel
+    set result [list ""]
+    # check the files in the small file buffer
+    lappend result "file1 [string equal [tcltest::viewBinFile $vfs/file1] [lindex $datas 0]]"
+    lappend result "file2 [string equal [tcltest::viewBinFile $vfs/file2] [lindex $datas 1]]"
+    lappend result "file3 [string equal [tcltest::viewBinFile $vfs/file3] [lindex $datas 2]]"
+    # flush the files to pages
+    vfs::unmount $vfs
+    set h [vfs::cookfs::Mount -readonly $vfs $vfs]
+    # read the files again
+    lappend result "file1 [string equal [tcltest::viewBinFile $vfs/file1] [lindex $datas 0]]"
+    lappend result "file2 [string equal [tcltest::viewBinFile $vfs/file2] [lindex $datas 1]]"
+    lappend result "file3 [string equal [tcltest::viewBinFile $vfs/file3] [lindex $datas 2]]"
+    vfs::unmount $vfs
+    lappend result {}
+    join $result \n
+} -cleanup {
+    catch { vfs::unmount $vfs }
+    catch { close $channel }
+    tcltest::removeFile $vfs
+    tcltest::removeFile $file1
+    tcltest::removeFile $file2
+}  -result {
+file1 1
+file2 1
+file3 1
+file1 1
+file2 1
+file3 1
+}
+
+tcltest::test cookfsWriter-1.2 "Add big files" -setup {
+    set vfs [tcltest::makeFile {} pages.cfs]
+} -body {
+    set datas [randomDatas 3 1024]
+    set file1 [tcltest::makeBinFile [lindex $datas 0] file1]
+    set file2 [tcltest::makeBinFile [lindex $datas 1] file2]
+    set h [vfs::cookfs::Mount $vfs $vfs -pagesize 512 -smallfilesize 512 -smallfilebuffer 16384 -compression none]
+    set channel [open $file1 rb]
+    $h writeFiles file1 channel $channel "" file2 file $file2 "" file3 data [lindex $datas 2] ""
+    close $channel
+    set result [list ""]
+    # check the files in the small file buffer
+    lappend result "file1 [string equal [tcltest::viewBinFile $vfs/file1] [lindex $datas 0]]"
+    lappend result "file2 [string equal [tcltest::viewBinFile $vfs/file2] [lindex $datas 1]]"
+    lappend result "file3 [string equal [tcltest::viewBinFile $vfs/file3] [lindex $datas 2]]"
+    # flush the files to pages
+    vfs::unmount $vfs
+    set h [vfs::cookfs::Mount -readonly $vfs $vfs]
+    # read the files again
+    lappend result "file1 [string equal [tcltest::viewBinFile $vfs/file1] [lindex $datas 0]]"
+    lappend result "file2 [string equal [tcltest::viewBinFile $vfs/file2] [lindex $datas 1]]"
+    lappend result "file3 [string equal [tcltest::viewBinFile $vfs/file3] [lindex $datas 2]]"
+    vfs::unmount $vfs
+    lappend result {}
+    join $result \n
+} -cleanup {
+    catch { vfs::unmount $vfs }
+    tcltest::removeFile $vfs
+    tcltest::removeFile $file1
+    tcltest::removeFile $file2
+} -result {
+file1 1
+file2 1
+file3 1
+file1 1
+file2 1
+file3 1
+}
+
+tcltest::test cookfsWriter-2.1 "Error while adding files without parent directory" -setup {
+    set vfs [tcltest::makeFile {} pages.cfs]
+} -body {
+    set h [vfs::cookfs::Mount $vfs $vfs -compression none]
+    $h writeFiles file1 data x "" somedirectory/file2 data y ""
+} -cleanup {
+    vfs::unmount $vfs
+    tcltest::removeFile $vfs
+} -returnCodes error -result {unable to add "somedirectory/file2": Unable to create entry}
+
+tcltest::test cookfsWriter-3.1 "Add the same file while previous file is in small buffer" -setup {
+    set vfs [tcltest::makeFile {} pages.cfs]
+} -body {
+    set datas [randomDatas 3 1024]
+    set h [vfs::cookfs::Mount $vfs $vfs -pagesize 4096 -smallfilesize 4096 -smallfilebuffer 16384 -compression none]
+    $h writeFiles file1 data [lindex $datas 0] "" file1 data [lindex $datas 1] "" file1 data [lindex $datas 2] ""
+    set result [list ""]
+    # check the file in the small file buffer
+    lappend result "file1 [string equal [tcltest::viewBinFile $vfs/file1] [lindex $datas 2]]"
+    # flush the file to pages
+    vfs::unmount $vfs
+    set fs [file size $vfs]
+    # the file size should be (1 data [1024 bytes] + internal data) and less than (2 datas [2048 bytes])
+    lappend result [expr {($fs > 1024) && ($fs < 2048)}]
+    set h [vfs::cookfs::Mount -readonly $vfs $vfs]
+    # read the file again
+    lappend result "file1 [string equal [tcltest::viewBinFile $vfs/file1] [lindex $datas 2]]"
+    vfs::unmount $vfs
+    lappend result {}
+    join $result \n
+} -cleanup {
+    catch { vfs::unmount $vfs }
+    tcltest::removeFile $vfs
+} -returnCodes ok -result {
+file1 1
+1
+file1 1
+}
+
+tcltest::test cookfsWriter-3.2 "Add the same file while previous file in in pages" -setup {
+    set vfs [tcltest::makeFile {} pages.cfs]
+} -body {
+    set datas [randomDatas 3 1024]
+    set h [vfs::cookfs::Mount $vfs $vfs -pagesize 1024 -smallfilesize 1024 -smallfilebuffer 1024 -compression none]
+    $h writeFiles file1 data [lindex $datas 0] "" file1 data [lindex $datas 1] "" file1 data [lindex $datas 2] ""
+    set result [list ""]
+    # check the file
+    lappend result "file1 [string equal [tcltest::viewBinFile $vfs/file1] [lindex $datas 2]]"
+    # flush the file to pages
+    vfs::unmount $vfs
+    set fs [file size $vfs]
+    # the file size should be (3 datas [3072 bytes] + internal data)
+    lappend result [expr { $fs > ( 1024 * 3 ) }]
+    set h [vfs::cookfs::Mount -readonly $vfs $vfs]
+    # read the files again
+    lappend result "file1 [string equal [tcltest::viewBinFile $vfs/file1] [lindex $datas 2]]"
+    vfs::unmount $vfs
+    lappend result {}
+    join $result \n
+} -cleanup {
+    catch { vfs::unmount $vfs }
+    tcltest::removeFile $vfs
+} -returnCodes ok -result {
+file1 1
+1
+file1 1
+}
+
+tcltest::test cookfsWriter-4.1 "Error while adding file by absolute name" -setup {
+    set vfs [tcltest::makeFile {} pages.cfs]
+} -body {
+    set h [vfs::cookfs::Mount $vfs $vfs]
+    $h writeFiles /file1 data x ""
+} -cleanup {
+    vfs::unmount $vfs
+    tcltest::removeFile $vfs
+} -returnCodes error -result {unable to add "/file1": Unable to create entry}
+
+tcltest::test cookfsWriter-5.1 "Channel options for added channels are preserved" -setup {
+    set vfs [tcltest::makeFile {} pages.cfs]
+    set data1 [lindex [randomDatas 1 1024] 0]
+    set file1 [tcltest::makeBinFile $data1 file1]
+    set data2 [lindex [randomDatas 1 4096] 0]
+    set file2 [tcltest::makeBinFile $data2 file2]
+} -body {
+    set result [list ""]
+    # check small file
+    set h [vfs::cookfs::Mount $vfs $vfs -pagesize 2048 -smallfilesize 2048 -smallfilebuffer 16384 -compression none]
+
+    set channel [open $file1 r]
+    fconfigure $channel -encoding cp866 -translation cr
+    $h writeFiles file1 channel $channel ""
+    lappend result "-encoding [string equal cp866 [fconfigure $channel -encoding]]"
+    lappend result "-translation [string equal cr [fconfigure $channel -translation]]"
+    close $channel
+
+    # try something else
+    set channel [open $file1 r]
+    fconfigure $channel -encoding utf-8 -translation lf
+    $h writeFiles file2 channel $channel ""
+    lappend result "-encoding [string equal utf-8 [fconfigure $channel -encoding]]"
+    lappend result "-translation [string equal lf [fconfigure $channel -translation]]"
+    close $channel
+
+    # check big file
+
+    set channel [open $file2 r]
+    fconfigure $channel -encoding cp866 -translation cr
+    $h writeFiles file3 channel $channel ""
+    lappend result "-encoding [string equal cp866 [fconfigure $channel -encoding]]"
+    lappend result "-translation [string equal cr [fconfigure $channel -translation]]"
+    close $channel
+
+    # try something else
+    set channel [open $file2 r]
+    fconfigure $channel -encoding utf-8 -translation lf
+    $h writeFiles file4 channel $channel ""
+    lappend result "-encoding [string equal utf-8 [fconfigure $channel -encoding]]"
+    lappend result "-translation [string equal lf [fconfigure $channel -translation]]"
+    close $channel
+
+    vfs::unmount $vfs
+    lappend result {}
+    join $result \n
+} -cleanup {
+    catch { vfs::unmount $vfs }
+    catch { close $channel }
+    tcltest::removeFile $vfs
+    tcltest::removeFile $file1
+    tcltest::removeFile $file2
+} -result {
+-encoding 1
+-translation 1
+-encoding 1
+-translation 1
+-encoding 1
+-translation 1
+-encoding 1
+-translation 1
+}
+
+tcltest::test cookfsWriter-5.2 "Channel options are preserved when error occurs" -setup {
+    set vfs [tcltest::makeFile {} pages.cfs]
+    set data1 [lindex [randomDatas 1 1024] 0]
+    set file1 [tcltest::makeBinFile $data1 file1]
+} -body {
+    set result [list ""]
+    set h [vfs::cookfs::Mount $vfs $vfs -pagesize 2048 -smallfilesize 2048 -smallfilebuffer 16384 -compression none]
+
+    set channel [open $file1 r]
+    fconfigure $channel -encoding cp866 -translation cr
+    lappend result [catch { $h writeFiles dir/file1 channel $channel "" }]
+    lappend result "-encoding [string equal cp866 [fconfigure $channel -encoding]]"
+    lappend result "-translation [string equal cr [fconfigure $channel -translation]]"
+    close $channel
+
+    # try something else
+    set channel [open $file1 r]
+    fconfigure $channel -encoding utf-8 -translation lf
+    lappend result [catch { $h writeFiles dir/file2 channel $channel "" }]
+    lappend result "-encoding [string equal utf-8 [fconfigure $channel -encoding]]"
+    lappend result "-translation [string equal lf [fconfigure $channel -translation]]"
+    close $channel
+
+    vfs::unmount $vfs
+    lappend result {}
+    join $result \n
+} -cleanup {
+    catch { vfs::unmount $vfs }
+    catch { close $channel }
+    tcltest::removeFile $vfs
+    tcltest::removeFile $file1
+} -result {
+1
+-encoding 1
+-translation 1
+1
+-encoding 1
+-translation 1
+}
+
+tcltest::test cookfsWriter-6.1 "Deleting files in a small file buffer" -setup {
+    set vfs [tcltest::makeFile {} pages.cfs]
+} -body {
+    set result [list]
+    set data1 [lindex [randomDatas 1 1024] 0]
+    set data2 [lindex [randomDatas 1 4096] 0]
+    set h [vfs::cookfs::Mount $vfs $vfs -pagesize 2048 -smallfilesize 2048 -smallfilebuffer 16384 -compression none]
+    $h writeFiles file1 data $data1 ""
+    lappend result [file exists $vfs/file1]
+    file delete $vfs/file1
+    lappend result [file exists $vfs/file1]
+    # add some real file
+    $h writeFiles file2 data $data2 ""
+    vfs::unmount $vfs
+    set fs [file size $vfs]
+    # the file size should be (1 big data [4096 bytes] + internal data) and less than (1 big data + 1 small data [5120 bytes])
+    lappend result [expr {($fs > 4096) && ($fs < (1024 + 4096))}]
+    set h [vfs::cookfs::Mount -readonly $vfs $vfs]
+    # file1 doesn't exist
+    lappend result [file exists $vfs/file1]
+    # file2 exists
+    lappend result [file exists $vfs/file2]
+    vfs::unmount $vfs
+    set result
+} -cleanup {
+    catch { vfs::unmount $vfs }
+    tcltest::removeFile $vfs
+} -result {1 0 1 0 1}
+
+tcltest::test cookfsWriter-6.2 "Deleting files doesn't corrupt following files in small file buffer" -setup {
+    set vfs [tcltest::makeFile {} pages.cfs]
+} -body {
+    set result [list]
+    lassign [randomDatas 2 1024] data1 data2
+    set h [vfs::cookfs::Mount $vfs $vfs -pagesize 4096 -smallfilesize 4096 -smallfilebuffer 16384 -compression none]
+    $h writeFiles file1 data $data1 "" file2 data $data2 ""
+    lappend result [file exists $vfs/file1]
+    lappend result [file exists $vfs/file2]
+    lappend result "match=[string equal [tcltest::viewBinFile $vfs/file2] $data2]"
+    file delete $vfs/file1
+    lappend result [file exists $vfs/file1]
+    lappend result [file exists $vfs/file2]
+    lappend result "match=[string equal [tcltest::viewBinFile $vfs/file2] $data2]"
+    vfs::unmount $vfs
+    set fs [file size $vfs]
+    # the file size should be (1 data [1024 bytes] + internal data) and less than (2 datas [2048 bytes])
+    lappend result [expr {($fs > 1024) && ($fs < (1024 * 2))}]
+    set h [vfs::cookfs::Mount -readonly $vfs $vfs]
+    # file1 doesn't exist
+    lappend result [file exists $vfs/file1]
+    # file2 exists
+    lappend result [file exists $vfs/file2]
+    lappend result "match=[string equal [tcltest::viewBinFile $vfs/file2] $data2]"
+    vfs::unmount $vfs
+    set result
+} -cleanup {
+    catch { vfs::unmount $vfs }
+    tcltest::removeFile $vfs
+} -result {1 1 match=1 0 1 match=1 1 0 1 match=1}
+
+