Re: dd: add 'skip_bytes' and 'count_bytes' operands

[Pádraig Brady]

On 02/13/2012 07:50 AM, Bernhard Voelker wrote:
> On 02/10/2012 05:21 PM, Jérémy Compostella wrote:
> 
> Sorry, this is a bit late, but I have 2 notes about the
> new dd/bytes test:
> 
>> diff --git a/tests/dd/bytes b/tests/dd/bytes
>> new file mode 100755
>> index 0000000..6038742
>> --- /dev/null
>> +++ b/tests/dd/bytes
>> @@ -0,0 +1,57 @@
> 
>> +# seek bytes
>> +echo abcdefghijklm |
>> + dd bs=5 seek=8 oflag=seek_bytes > out 2> /dev/null || fail=1
>> +echo abcdefghijklm |
>> + dd bs=4 seek=2 > expected 2> /dev/null || fail=1
>> +compare expected out || fail=1
> 
> I don't know why, but I somehow do not have a good feeling
> about a test comparing the result of the program to be tested
> with another run. If something cowardly fails, then this test
> would succeed.

Fair point.

>> +# seek bytes on empty file
>> +echo abcdefghijklm |
>> + dd bs=5 seek=8 oflag=seek_bytes > out2 2> /dev/null || fail=1
>> +compare expected out2 || fail=1
> 
> The comment is wrong here, isn't it?

Well out2 will be a new empty file.
Though the case is no different to the previous
(since conv=notrunc was not specified).
So I'll just remove it.

cheers,
Pádraig.

diff --git a/tests/dd/bytes b/tests/dd/bytes
index 6038742..10f3618 100755
--- a/tests/dd/bytes
+++ b/tests/dd/bytes
@@ -45,13 +45,7 @@ esac
 # seek bytes
 echo abcdefghijklm |
  dd bs=5 seek=8 oflag=seek_bytes > out 2> /dev/null || fail=1
-echo abcdefghijklm |
- dd bs=4 seek=2 > expected 2> /dev/null || fail=1
+printf '\0\0\0\0\0\0\0\0abcdefghijklm\n' > expected
 compare expected out || fail=1

-# seek bytes on empty file
-echo abcdefghijklm |
- dd bs=5 seek=8 oflag=seek_bytes > out2 2> /dev/null || fail=1
-compare expected out2 || fail=1
-
 Exit $fail