grep output prints only single line in bash script [duplicate]

Question

How can I get the results from grep to print on their own line in a bash script?

When using grep in the terminal, the output appears how I wish it would appear.

For instance:

$ whois x.x.85.72 | grep 'OrgName\|NetRange\|inetnum\|IPv4'
NetRange:       x.x.85.64 - x.x.85.95
NetRange:       x.x.0.0 - x.x.255.255
OrgName:        xxxxx Technologies Inc.

When using the same grep command in bash it prints out on one line.

The output of my bash script:

$ lookup xx.com
xx.com resolves to: x.x.85.72
NetRange: x.x.85.64 - x.x.85.95 NetRange: x.x.0.0 - x.x.255.255 OrgName:xxxxx Technologies Inc.

My bash script:

#! /bin/bash
VAR1="$1"

IP=`net lookup $VAR1`
echo $VAR1 resolves to: $IP
RANGE=`whois $IP | grep 'OrgName\|NetRange\|inetnum\|IPv4'`
echo $RANGE

aside from a solution, can anyone tell me why it does this?

Thanks a bunch!

fedorqui · Accepted Answer · 2013-09-25 13:24:10Z

10

You need to quote the variable to have the format preserved:

echo "$RANGE"

instead of

echo $RANGE

All together:

#!/bin/bash <--- be careful, you have an space after ! in your code
VAR1="$1"

IP=$(net lookup $VAR1) #<--- note I use $() rather than ``
echo $VAR1 resolves to: $IP
RANGE=$(whois $IP | grep 'OrgName\|NetRange\|inetnum\|IPv4')
echo "$RANGE"

Example

Given this:

$ date; date
Wed Sep 25 15:18:39 CEST 2013
Wed Sep 25 15:18:39 CEST 2013

Let's print its result with and without quotes:

$ myvar=$(date; date)
$ echo $myvar
Wed Sep 25 15:18:45 CEST 2013 Wed Sep 25 15:18:45 CEST 2013
$ echo "$myvar"
Wed Sep 25 15:18:45 CEST 2013
Wed Sep 25 15:18:45 CEST 2013

edited Sep 25, 2013 at 13:24

answered Sep 25, 2013 at 13:17

fedorqui

293k113 gold badges592 silver badges640 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Chris Seymour · Accepted Answer · 2013-09-25 13:25:45Z

2

Quoting is very important in the shell, you need to quote all your variables to preserve the newlines:

#!/bin/bash

VAR1="$1"

IP=$(net lookup "$VAR1")
echo "$VAR1 resolves to: $IP"
RANGE=$(whois "$IP" | egrep 'OrgName|NetRange|inetnum|IPv4')
echo "$RANGE"

Read man bash under the quoting section. Also using $() is much clearer than using backticks and it allows nesting.

edited Sep 25, 2013 at 13:25

answered Sep 25, 2013 at 13:17

Chris Seymour

86.4k32 gold badges166 silver badges209 bronze badges

Comments

Atropo · Accepted Answer · 2013-09-25 13:18:12Z

1

You're missing the quote of the $RANGE variable.

You should use:

echo "$RANGE"

Without the quote the newline isn't preserved.

answered Sep 25, 2013 at 13:18

Atropo

12.6k8 gold badges51 silver badges62 bronze badges

Comments

Vlad · Accepted Answer · 2013-09-25 13:18:23Z

1

Replace:

RANGE=`whois $IP | grep 'OrgName\|NetRange\|inetnum\|IPv4'`
echo $RANGE

with

whois $IP | grep 'OrgName\|NetRange\|inetnum\|IPv4'

or

RANGE=`whois $IP | grep 'OrgName\|NetRange\|inetnum\|IPv4'`
echo "$RANGE"

answered Sep 25, 2013 at 13:18

Vlad

1,1978 silver badges15 bronze badges

Collectives™ on Stack Overflow

grep output prints only single line in bash script [duplicate]

4 Answers 4

Example

Comments

Comments

Comments

Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

Example

Comments

Comments

Comments

Comments

Linked

Related