在Yocto项目中，我可以看到可用的图层：
$ bitbake-layers show-layers
NOTE: Starting bitbake server...
layer path priority
==========================================================================
meta-oe /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/meta-openembedded/meta-oe 6
meta-gnome /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/meta-openembedded/meta-gnome 7
meta-xfce /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/meta-openembedded/meta-xfce 7
meta-initramfs /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/meta-openembedded/meta-initramfs 8
meta-multimedia /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/meta-openembedded/meta-multimedia 6
meta-networking /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/meta-openembedded/meta-networking 5
meta-webserver /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/meta-openembedded/meta-webserver 6
meta-filesystems /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/meta-openembedded/meta-filesystems 6
meta-perl /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/meta-openembedded/meta-perl 6
meta-python /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/meta-openembedded/meta-python 7
meta-st-stm32mp /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/meta-st/meta-st-stm32mp 6
meta-qt5 /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/meta-qt5 7
meta-st-openstlinux /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/meta-st/meta-st-openstlinux 5
meta /local/STM32MP15-Ecosystem-v1.0.0/Distribution-Package/openstlinux-4.19-thud-mp1-19-02-20/layers/openembedded-core/meta 5
现在我尝试删除其中一些：
$ bitbake-layers remove-layer meta-gnome meta-xfce meta-multimedia
NOTE: Starting bitbake server...
No layers matching */meta-xfce found in BBLAYERS
No layers matching */meta-gnome found in BBLAYERS
No layers matching */meta-multimedia found in BBLAYERS
如果在show-layers命令中显示了它们，为什么找不到它们？