fx set-build-dir

设置其他 fx 命令使用的默认 build 目录

usage: fx set-build-dir DIR
   or: fx --dir DIR set-build-dir
   or: fx set-buil-dir

Switches further `fx` commands to using a different build directory.
This only works if `fx --dir DIR set ...` succeeded previously
(and DIR has not been removed since).  The next `fx build` or other
such command will now refer to DIR.  The previous build directory is
left in place, so you can switch back again with `fx set-build-dir` later.

fx set-build-dir without arguments will list the available build directories, naming
the current active build directory (if any).

set-build-dir 源代码