What we did above is called "command substitution".

上面所做的称为“命令替换”。

youdao

This string is then written back into the timestamp line by the substitution command.

这个字符串然后被替代命令写回时间戳。

youdao

This string is then written back into the timestamp line by the substitution command.

这个字符串然后被替代命令写回时间戳。

youdao