ld: symbol(s) not found for architecture arm64

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keyallis OP

Created 1d

Replies 2

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Participants 3

I'm attempting to determine whether there is a currently logged on user via the SCDynamicStoreCopyConsoleUser function.

My code look something along the lines of:

#include <SystemConfiguration/SystemConfiguration.h>

bool isUserLoggedOn()
{
    CFStringRef name = SCDynamicStoreCopyConsoleUser(NULL, NULL, NULL);
    if (name != NULL)
    {
        CFRelease(name);
        return true;
    }
    return false;
}

I am getting the following error output on compilation:

Undefined symbols for architecture arm64:
    "_CFRelease", referenced from:
        isUserLoggedOn() in UserInfo.cpp.o
    "_SCDynamicStoreCopyConsoleUser", referenced from:
        isUserLoggedOn() in UserInfo.cpp.o
ld: symbol(s) not found for architecture arm64

Answered by DTS Engineer in 797230022

You're likely missing a reference to the SystemConfiguration framework in the Link Binary with Libraries build phase.

— Ed Ford,  DTS Engineer

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Answer 1

DTS Engineer OP

Apple

1d

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You're likely missing a reference to the SystemConfiguration framework in the Link Binary with Libraries build phase.

— Ed Ford,  DTS Engineer

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Answer 2

DTS Engineer OP

Apple

23h

Assuming you get your linking issue sorted out (thanks Ed!), I’d like to get a better idea of what you’re doing with SCDynamicStoreCopyConsoleUser. It’s a tricky API because:

There can be zero or more logged in GUI users.
They can be a mixture of local (via Fast User Switching) and remote (via Screen Sharing) users.

Many folks I see trying to use this routine don’t understand these subtleties, and thus write code that breaks when it encounter some the first time.

So, what are you expecting to do with SCDynamicStoreCopyConsoleUser?

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Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

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