Bash脚本回显，无需按Enter

Question

Edit : Current code

#!/bin/bash
check=0

while [ $check -ne 1 ];
do
        ping -c 1 192.168.150.1 >> /dev/null
        if [ $? -eq 0 ];then
            echo -ne "\nClient is up! We will start the web server"
            touch /etc/apache2/httpd.conf
            echo "ServerName 127.0.0.1" > /etc/apache2/httpd.conf
            /etc/init.d/apache2 start
            if [ $? -eq 0 ];then
            exit 0
            fi
        else
            echo -ne "\nWaiting for client to come online"
            sleep 5;
        fi
done

I am currently learning some Bash scripting and I want to be able to echo it to the terminal and without having to press enter to then continue with the terminal.

For example... If I echo "We are working" the cursor will go to the end and wait for me to press Enter to then return me back to where I could type a new command.

server:#
Waiting for client to come online
Waiting for client to come online
Waiting for client to come online
Waiting for client to come online
Waiting for client to come online
Waiting for client to come online
Waiting for client to come online
Waiting for client to come online
Waiting for client to come online <---- Press Enter here
server:#

Answer 1

I suspect your issue is related to using echo -ne '\\n...' instead of simply echo '...' . However, your whole code can be simplified greatly:

#!/bin/bash

while :; do
    until ping -c 1 192.168.150.1 > /dev/null; do
        echo "Waiting for client to come online"
    done
    echo "Client is up! We will start the web server"
    echo "ServerName 127.0.0.1" > /etc/apache2/httpd.conf
    /etc/init.d/apache2 start && break
done

Answer 2

Use echo "^M".

The character inside quoted is formed by pressing crtl+v+m.

It should work.

This character will do the job of enter.

Update:

I just tried it on my shell. I am able to get the extra enter. you may need to put another echo command after that.

To check, we use "od -c" (as shown below), whether the character has correctly formed or not.

With proper character, we get "\\r \\n" in od -c output. And in improper one, we get ^ M.

Proper:

Wed Oct 05|19:03:45|app/ga> echo "^M"|od -c
0000000  \r  \n
0000002

Improper:

Wed Oct 05|19:03:50|app/ga> echo "^M"|od -c
0000000   ^   M  \n
0000003
Wed Oct 05|19:03:57|app/ga>

After having verified that, please give another try with this line, instead of your line in the script.

echo -ne "\nWaiting for client to come online" ; echo "^M"

Where "^M" character is properly formed by pressing ctrl+v+m on keyboard.

Cheers , Gaurav