macOS: accessing /var/log/jamf.log with sandboxed app

I'm trying to parse /var/log/jamf.log (line by line), while having a sandboxed application.

My entitlements file:

    <dict>
    <key>com.apple.security.app-sandbox</key>
    <true/>
    <key>com.apple.security.temporary-exception.files.absolute-path.read-write</key>
        <array>
            <string>/var/log/jamf.log</string>
        </array>
    </dict>

(I also tried with .read-only)

Running code:

    do {
        self.logFileHandle = try FileHandle(forReadingFrom: URL(fileURLWithPath: "/var/log/jamf.log", isDirectory: false))
    } catch {
        dump(error)
        self.logFileHandle = nil
    }

With this, I get the following error:

> Error Domain=NSCocoaErrorDomain Code=1 "(null)"

> UserInfo={NSFilePath=/var/log/jamf.log}

Anyone has an idea? Is it possible that / corresponds to the root of the sandbox?

Thanks!

François

PS: Also asked on http://stackoverflow.com/questions/42585294/accessing-var-log-jamf-log-with-sandboxed