使用“！"在脚本中执行具有相同参数的命令 [英] use "!" to execute commands with same parameter in a script

问题描述

在 shell 中，我运行以下命令没有问题，

In a shell, I run following commands without problem,

ls -al

!ls

对 ls 的第二次调用也会列出带有 -al 标志的文件.但是，当我把上面的脚本放到 bash 脚本中时，就会抛出抱怨，

the second invocation to ls also list files with -al flag. However, when I put the above script to a bash script, complaints are thrown,

!ls，未找到命令.

如何在脚本中实现同样的效果?

how to realise the same effects in script?

推荐答案

您需要在脚本中同时打开命令历史记录和 !-style 历史记录扩展(在非交互式 shell 中默认情况下这两个都是关闭的):

You would need to turn on both command history and !-style history expansion in your script (both are off by default in non-interactive shells):

set -o history
set -o histexpand

扩展的命令也会回显到标准错误，就像在交互式 shell 中一样.您可以通过打开 histverify shell 选项 (shopt -s histverify) 来防止这种情况发生，但在非交互式 shell 中，这似乎使历史扩展为空-操作.

The expanded command is also echoed to standard error, just like in an interactive shell. You can prevent that by turning on the histverify shell option (shopt -s histverify), but in a non-interactive shell, that seems to make the history expansion a null-op.

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