如何在不执行命令的情况下从Shell脚本在命令提示符下输入文本？

Question

Is there a way to have a shell script output text at the command prompt WITHOUT issuing the command?

CONTEXT: I SSH into a particular machine several times a day, and about 80% of the time, I type the same three commands as soon as I login. I would just put these commands in my .bashrc , but 20% of the time, I do NOT want to issue these commands. I'm wondering if there is some command I can put in .bashrc that will automatically put a string at my command line, so that when I login I see:

$ cd some/dir && ./some_script.sh

I could then just press enter 80% of the time or just clear the text the other 20% of the time.

Answer 1

I know this is not what you asked but why don't use alias to shorten your command?

$ alias a='cd some/dir && ./some_script.sh'

Since you are going to use this often you could add this to you .bashrc file, so you don't have to set the alias every time.
After login you could just type a

$ a

Answer 2

(Inspired by Abdul Rehman's answer.)

Put this as the last line in your .bashrc file:

read -e -p "(Control-C to cancel) $ " -i "cd some/dir && ./some_script.sh" && eval "$REPLY"

• read -e lets you enter a string using Readline for editing.
• The -p provides a pseudo-prompt for this one-time command.
• The -i provides a default string which you can edit or hit Enter to accept.

If you hit Enter, read sets the value of REPLY and exits with status 0, causing the following eval to execute. (Usually, eval is not a good command to use; however, here you would be presented with an interactive shell anyway, so there's not much risk here.) If you type Control - C instead, read exits with status 1 and the following eval is not executed, leaving you at your command prompt.

Answer 3

Put this script in .bashrc. It will ask you to run this command.

while true; do
read -p "Run this command?" yn
case $yn in
    [Yy]* ) cd some/dir && ./some_script.sh; break;;
    [Nn]* ) break;;
    * ) echo "Enter Yes or No."
esac
done

Answer 4

I don't know of a way to do that but you could use history -s to push that command/those commands into the history when you log in which would then let you use !!<cr> or <up><cr> to execute them and just proceed normally if you don't.

history -s cd some/dir '&&' ./some_script.sh

You need to quote anything that the shell would normally evaluate/expand/remove. So the && in that example, any quotes, any semicolons, etc.

Answer 5

You can run script on remote server instead loggin via ssh:

ssh <SERVER> some/dir/some_script.sh

For the remaining 20% you can connect ssh as usual.