close $f
    set x
} "\r\n12"
test io-3.4 {WriteChars: loop over stage buffer} -body {
    # stage buffer maps to more than can be queued at once.

    set f [open $path(test1) w]
    fconfigure $f -encoding jis0208 -buffersize 16 -nocomplainencoding 1
    puts -nonewline $f "\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"
    set x [list [contents $path(test1)]]
    close $f
    lappend x [contents $path(test1)]
} -cleanup {
    catch {close $f}
} -result [list "!)!)!)!)!)!)!)!)" "!)!)!)!)!)!)!)!)!)!)!)!)!)!)!)"]
test io-3.5 {WriteChars: saved != 0} -body {
    # Bytes produced by UtfToExternal from end of last channel buffer
    # had to be moved to beginning of next channel buffer to preserve
    # requested buffersize.

    set f [open $path(test1) w]
    fconfigure $f -encoding jis0208 -buffersize 17 -nocomplainencoding 1
    puts -nonewline $f "\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"
    set x [list [contents $path(test1)]]
    close $f
    lappend x [contents $path(test1)]
} -cleanup {
    catch {close $f}
} -result [list "!)!)!)!)!)!)!)!)!" "!)!)!)!)!)!)!)!)!)!)!)!)!)!)!)"]

    # When translating UTF-8 to external, the produced bytes went past end
    # of the channel buffer.  This is done purpose -- we then truncate the
    # bytes at the end of the partial character to preserve the requested
    # blocksize on flush.  The truncated bytes are moved to the beginning
    # of the next channel buffer.

    set f [open $path(test1) w]
    fconfigure $f -encoding jis0208 -buffersize 17 -nocomplainencoding 1
    puts -nonewline $f "\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"
    set x [list [contents $path(test1)]]
    close $f
    lappend x [contents $path(test1)]
} -cleanup {
    catch {close $f}
} -result [list "!)!)!)!)!)!)!)!)!" "!)!)!)!)!)!)!)!)!)!)!)!)!)!)!)"]