LinuxQuestions.org - What is wrong in the statement: $line || echo "error" && break;

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- - What is wrong in the statement: $line || echo "error" && break; (https://www.linuxquestions.org/questions/linux-general-1/what-is-wrong-in-the-statement-%24line-%7C%7C-echo-error-and-and-break%3B-470976/)

What is wrong in the statement: $line || echo "error" && break;

I did a little script to execute commands:

Code:

#!/bin/bash

exec < $1

while read line;

do      

        $line || echo "error" && break;

done

The problem is that the loop break after the first time.

what is the problem?

if $line is work fine, it is not supposed to execute the right side of the OR gate.

if $line is failed, it's supposed to continue the echo "error" and this is should to return true and only then execute the break.

if I use:

Code:

#!/bin/bash

exec < $1

while read line;

do      

        $line || break;

done

it's work good.

and also this code:

Code:

#!/bin/bash

exec < $1

while read line;

do



        $line || !(echo "error") || break;

done

Aren't both operators of equal precedence? If they are, it executes from left to right, evaluating the || first and if either one was true it does the &&, causing the break. In effect it acts like:

Code:

($line || echo "error") && break

But you want it to behave like:

Code:

$line || ( echo "error" && break)

Those brackets are only me trying to explain what is happening, I haven't checked whether you can group operations like that with them.