在 linux 内核编译的时候，有时候会遇到内核编译选项配置缺失，导致输入编译命令时需要输入 'Enter' 键，尤其是编译选项一多就要连续输入多个 'Enter' 键。
在多项目开发的时候比较常见。由于多项目开发，添加一个内核配置选项，就影响到全部项目的编译。但又不能直接修改其他项目的内核编译选项。这就造成编译的麻烦。
比如下面这种
Caching block device access to MTD devices (MTD_BLOCK) [Y/n/m/?] y
FTL (Flash Translation Layer) support (FTL) [N/m/y/?] n
NFTL (NAND Flash Translation Layer) support (NFTL) [N/m/y/?] n
INFTL (Inverse NAND Flash Translation Layer) support (INFTL) [N/m/y/?] n
Resident Flash Disk (Flash Translation Layer) support (RFD_FTL) [N/m/y/?] n
NAND SSFDC (SmartMedia) read only translation layer (SSFDC) [N/m/y/?] n
SmartMedia/xD new translation layer (SM_FTL) [N/m/y/?] n
Log panic/oops to an MTD buffer (MTD_OOPS) [N/m/y/?] n
Swap on MTD device support (MTD_SWAP) [N/m/y/?] n
Retain master device when partitioned (MTD_PARTITIONED_MASTER) [N/y/?] n
SUPPORT SKIP SQUASHFS PARTITION BAD BLOCK (SKIP_SQUASHFS_BAD_BLOCK) [N/y/?] n
Using GPIO as CS1 in dual nor case(567 series only) (GPIO_CS) [Y/n/m/?] y
Trusted Execution Environment support (TEE) [N/m/y/?] n
SUPPORT MCU WAKE AOV FRAME CAPTURE (TAPO_MCU_WAKE_AOV_FRAME) [N/y/?] (NEW)
GET DECS INFO. (MULTI_DCE) [N/y/?] (NEW)
因此可以使用下面的 command
echo | command
自动输入 'Enter' 键
参考链接：https://worktile.com/kb/ask/362191.html