echo 1 / sys / bus / pci / slots / $ 4 / potência bash: / sys / bus / pci / slots // energia: Permissão negada

Question

Ao digitar echo 1 > /sys/bus/pci/slots/$4/power , recebo este erro:

bash: /sys/bus/pci/slots//power: Permission denied

Aqui está a saída de lscpi -vv no meu sistema:

02:00.0 Multimedia controller: Digital Devices GmbH Octopus DVB Adapter
        Subsystem: Digital Devices GmbH Cine S2 V6.5 DVB adapter
        Physical Slot: 4
        Flags: fast devsel, IRQ 46
        Memory at c7400000 (64-bit, non-prefetchable) [size=64K]
        Capabilities: [50] Power Management version 3
        Capabilities: [70] MSI: Enable+ Count=2/2 Maskable- 64bit+
        Capabilities: [90] Express Endpoint, MSI 00
        Capabilities: [100] Vendor Specific Information: ID=0000 Rev=0 Len=00c <?>
        Kernel driver in use: ddbridge

06:00.0 Multimedia controller: Digital Devices GmbH Max
        Subsystem: Digital Devices GmbH Max S8 4/8
        Physical Slot: 3
        Flags: fast devsel, IRQ 49
        Memory at c7300000 (64-bit, non-prefetchable) [size=64K]
        Capabilities: [50] Power Management version 3
        Capabilities: [70] MSI: Enable+ Count=2/2 Maskable- 64bit+
        Capabilities: [90] Express Endpoint, MSI 00
        Capabilities: [100] Vendor Specific Information: ID=0000 Rev=0 Len=00c <?>
        Kernel driver in use: ddbridge

    

Answer 1

echo não funciona assim.

Você precisaria usar sudo tee para permitir permissão:

echo 1 | sudo tee /sys/bus/pci/slots/4/power

Além disso, acho que você provavelmente quis especificar o slot 4, que seria 4 em vez de $ 4.