如何启用脚本中 shell 命令的彩色输出？

基本上，假设我有一个像这样的命令grep它输出带有类似标志的颜色编码结果-r。如果我将此命令包装在 shell 脚本中，则在运行该脚本时，输出将不会具有相同的颜色编码效果。

有没有其他方法可以使 shell 脚本以相同的颜色编码吐出结果（在终端上），而无需使用tput或者手动颜色编码？

强制颜色输出grep:

grep --color=always

From man grep:

   --color[=WHEN], --colour[=WHEN]
          Surround   the   matched   (non-empty)   strings,
          matching lines, context lines, file  names,  line
          numbers, byte offsets, and separators (for fields
          and  groups  of  context   lines)   with   escape
          sequences   to  display  them  in  color  on  the
          terminal.   The  colors  are   defined   by   the
          environment variable GREP_COLORS.  The deprecated
          environment   variable   GREP_COLOR   is    still
          supported,   but   its   setting  does  not  have
          priority.  WHEN is never, always, or auto.