.config some_variables

root@rescue ~ # cat /mnt/gentoo/usr/src/linux/.config | grep AHCI
CONFIG_SATA_AHCI=y
# CONFIG_SATA_AHCI_PLATFORM is not set
# CONFIG_SATA_ACARD_AHCI is not set
root@rescue ~ # cat /mnt/gentoo/usr/src/linux/.config | grep EXT4
CONFIG_EXT4_FS=y
CONFIG_EXT4_FS_POSIX_ACL=y
# CONFIG_EXT4_FS_SECURITY is not set
# CONFIG_EXT4_DEBUG is not set
root@rescue ~ # cat /mnt/gentoo/usr/src/linux/.config | grep EXT3
CONFIG_EXT3_FS=y
CONFIG_EXT3_DEFAULTS_TO_ORDERED=y
CONFIG_EXT3_FS_XATTR=y
CONFIG_EXT3_FS_POSIX_ACL=y
# CONFIG_EXT3_FS_SECURITY is not set
root@rescue ~ # cat /mnt/gentoo/usr/src/linux/.config | grep EXT2
CONFIG_EXT2_FS=y
CONFIG_EXT2_FS_XATTR=y
CONFIG_EXT2_FS_POSIX_ACL=y
# CONFIG_EXT2_FS_SECURITY is not set
# CONFIG_EXT2_FS_XIP is not set