Re: Help with fetchmail bug #268228

[Adeodato Simó <asp16@alu.ua.es>]

* Graham Wilson [Sun, 29 Aug 2004 21:12:59 -0500]:

> Upon upgrading from multi-package version of fetchmail to the
> latest version, fetchmail-common is removed from the system, and removes
> the fetchmail user as well.

  [relevant information: fetchmail provides, replaces and conflicts
  fetchmail-common.]

  most likely, the 'fetchmail' user won't get removed; only if the user
  passes --purge to apt-get or whatever. which you mostly want to
  happen, since the 'fetchmail' user will be created again in the
  fetchmail.postinst script in the same apt-get run.

  so the real problem is, as in the bug report, when the user purges the
  -common package (which will be in state 'removed') *after* the
  transition split packages ==> single packages has happened.

> What is the best way to fix this? This only way I can think of (as was
> suggested in #268228) is to check in the init script whether the user
> exists, and, if not, to create it.

  I can think of three other alternatives:
    
    (a) re-introduce the fetchmail-common package as a dummy package,
    and make the fetchmail package (versioned) depend on it.

    (b) re-introduce the fetchmail-common package, make the fetchmail
    package conflict with fetchmail-common << 6.2.5 or so and put in the
    f-common description somethink like:  "Dummy package to help
    transition from woody. You may safely purge this package once it has
    been installed."

    (c) <evil mode> in the fetchmail.postinst script, put some code
    equivalent to "echo >/var/lib/dpkg/info/fetchmail-common.postinst"
    (if the file exists), neutralizing the parts of it you never want
    executed anymore. (does policy forbid that?)

  all have their pros and cons, and perhaps the original init.d one,
  being uglier, is more robust that these ones. but it *really* does not
  address the problem of having not-to-be-executed code in
  fetchmail-common.postinst for an unknown amount of time (when would
  you remove the check from the script?) I wrote my alternatives with
  that issue in mind (the -common package could go right after sarge
  releases, and so the hackery in f.postinst).

  cheers,

-- 
Adeodato Simó
    EM: asp16 [ykwim] alu.ua.es | PK: DA6AE621
 
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