Frederik Eaton wrote:
Hi,
I tried installing Cabal-1.1.4, but a bug from a long time ago is still present. Is it the case that if the new Cabal is in my package database, then it will be used?
$ ghc-pkg list /home/frederik/arch/i386//lib/ghc-6.4.2/package.conf: Cabal-1.1.4, GLUT-2.0, HGL-3.1, HUnit-1.1, OpenGL-2.0, QuickCheck-1.0, X11-1.1, base-1.0, (concurrent-1.0), (data-1.0), fgl-5.2, haskell-src-1.0, haskell98-1.0, hsql-1.7, hsql-mysql-1.7, (hssource-1.0), (lang-1.0), mtl-1.0, (net-1.0), network-1.0, parsec-1.0, (posix-1.0), readline-1.0, rts-1.0, stm-1.0, template-haskell-1.0, (text-1.0), unix-1.0, (util-1.0) /home/frederik/.ghc/i386-linux-6.4.2/package.conf: Futility-0.1.8, GSL-0.5
The bug occurs when there is an existing file with the same path as one which Cabal is trying to install - rather than unlinking and creating a new file, it seems that Cabal tries to open the existing file and write to it.
... Skipping Main ( programs/move-spool.hs, dist/build/move-spool/move-spool-tmp/Main.o ) dist/build/move-spool/move-spool is up to date, linking not required. Installing: /home/frederik/lib/Futility-0.1.8/ghc-6.4.2 & /home/frederik/bin Futility-0.1.8... *** Exception: /home/frederik/bin/fssh: copyFile: resource busy (Text file busy)
I've fixed this in System.Directory.copyFile, although there doesn't seem to be a foolproof way to do it: if you unlink before opening, there's a chance that someone else can create the file in between. Still, this appears to be what install(3) does. Cheers, Simon