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    SubjectRe: Complaint about return code convention in queue_work() etc.
    >> > >I'd like to lodge a bitter complaint about the return codes used by
    >> > >queue_work() and related functions:
    >> > >
    >> > > Why do the damn things return 0 for error and 1 for success???
    >> > > Why don't they use negative error codes for failure, like
    >> > > everything else in the kernel?!!
    >> >
    >> > It's a standard programming idiom: return false (0) for failure, true
    >> > (non-zero) for success. Boolean.
    >>
    >> There are at least 3 idioms:
    >>
    >> 1) return 0 on success, -E on fail¹.
    >> 2) return 1 on YES, 0 on NO.
    >> 3) return valid pointer on OK, NULL on fail.

    I wrote something up some time ago,
    http://svn.sourceforge.net/viewvc/vitalnix/trunk/src/doc/extra-aee.php?revision=1

    >Functions can return values of many different kinds, and one of the most
    >common is a value indicating whether the function succeeded or failed.
    >Such a value can be represented as a "status" integer (0 = success, -Exxx
    >= failure) or a "succeeded" boolean (1 = success, 0 = failure).
    >
    >Mixing up these two sorts of representations is a fertile source of
    >difficult-to-find bugs. If the C language included a strong distinction
    >between integers and booleans then the compiler would find these mistakes
    >for us... but it doesn't.

    Recently introduced "bool".



    Jan Engelhardt
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