[Haskell-cafe] invalid character encoding

[Ian Lynagh]

On Tue, Mar 15, 2005 at 10:44:28AM +0000, Ross Paterson wrote:
> 
> You can select binary I/O using the openBinaryFile and hSetBinaryMode
> functions from System.IO.  After that, the Chars you get from that Handle
> are actually bytes.

What about the ones sent to it?
Are all the following results intentional?
Am I doing something stupid?

[in brief: hugs' (hPutStr h) now behaves differently to
 (mapM_ (hPutChar h)), and ghc writes the empty string for both when
 told to write "\128"]

Running the following with new ghc 6.4 and hugs 20050308 or 20050317:

echo 'import System.IO; import System.Environment; main = do [o] <- getArgs; ho <- openBinaryFile o WriteMode; hPutStr ho "\128"' > run1.hs
echo 'import System.IO; import System.Environment; main = do [o] <- getArgs; ho <- openBinaryFile o WriteMode; mapM_ (hPutChar ho) "\128"' > run2.hs
runhugs run1.hs hugs1
runhugs run2.hs hugs2
runghc run1.hs ghc1
runghc run2.hs ghc2
ls -l hugs1 hugs2 ghc1 ghc2
for f in hugs1 hugs2 ghc1 ghc2; do echo $f; hexdump -C $f; done

gives:

-rw-r--r--  1 igloo igloo 0 Mar 17 06:15 ghc1
-rw-r--r--  1 igloo igloo 0 Mar 17 06:15 ghc2
-rw-r--r--  1 igloo igloo 1 Mar 17 06:15 hugs1
-rw-r--r--  1 igloo igloo 1 Mar 17 06:15 hugs2
hugs1
00000000  3f                                                |?|
00000001
hugs2
00000000  80                                                |.|
00000001
ghc1
ghc2

With ghc 6.2.2 and hugs "November 2003" I get:

-rw-r--r--  1 igloo igloo 1 Mar 17 06:16 ghc1
-rw-r--r--  1 igloo igloo 1 Mar 17 06:16 ghc2
-rw-r--r--  1 igloo igloo 1 Mar 17 06:16 hugs1
-rw-r--r--  1 igloo igloo 1 Mar 17 06:16 hugs2
hugs1
00000000  80                                                |.|
00000001
hugs2
00000000  80                                                |.|
00000001
ghc1
00000000  80                                                |.|
00000001
ghc2
00000000  80                                                |.|
00000001


Incidentally, "make check" in CVS hugs said:

cd tests && sh testScript | egrep -v '^--( |-----)'
./../src/hugs +q -w -pHugs: static/mod154.hs < /dev/null
expected stdout not matched by reality
*** static/Loaded.output        Fri Jul 19 22:41:51 2002
--- /tmp/runtest11949.3 Thu Mar 17 05:46:05 2005
***************
*** 1,2 ****
! Type :? for help
  Hugs:[Leaving Hugs]
--- 1,3 ----
! ERROR "static/mod154.hs" - Conflicting exports of entity "sort"
! *** Could refer to Data.List.sort or M.sort
  Hugs:[Leaving Hugs]


Thanks
Ian