Solved

BASH - script problem

Posted on 2007-04-07
9
304 Views
Last Modified: 2013-12-26
h=0
while [ $h -eq 0 ]; do
if echo "$host" | egrep -e '^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$';
then
IFS='.'
arr=($host)
if [ ${arr[0]} -le 255 -a ${arr[1]} -le 255 -a ${arr[2]} -le 255 -a ${arr[3]} -le 255 ];
then
if [ ${arr[0]:0:1} !-eq 0 ] || [ ${arr[1]:0:1} !-eq 0 ] || [ ${arr[2]:0:1} !-eq 0 ]; then
h=1
IFS=''
fi
else
echo "Error: The maximum number you can write is 255, try again."
read host
fi
else
echo "Error: You MUST use only digits from 1 to 5, and the ip must be like xxx.xxx.xxx.xxx, try again."
read host
fi
done

Any ideea whats wrong in this ?
Should i put IFP='' after each else or something ? :|
0
Comment
Question by:rares_dumitrescu
  • 4
  • 3
  • 2
9 Comments
 
LVL 84

Expert Comment

by:ozo
ID: 18869092
h=0
while [ $h -eq 0 ]; do
  if echo "$host" | egrep -e '^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$';
  then
    IFS='.'
    arr=($host)
    if [ ${arr[0]} -le 255 -a ${arr[1]} -le 255 -a ${arr[2]} -le 255 -a ${arr[3]} -le 255 ];
    then
      if [ ! ${arr[0]:0:1} -eq 0 ] || [ ${arr[1]:0:1} -ne  0 ] || [ ! ${arr[2]:0:1} -eq 0 ]; then
        h=1
        IFS=''
      fi
    else
      echo "Error: The maximum number you can write is 255, try again."
      read host
    fi
  else
    echo "Error: You MUST use only digits from 1 to 5, and the ip must be like xxx.xxx.xxx.xxx, try again."
    read host
  fi
done
0
 

Author Comment

by:rares_dumitrescu
ID: 18869134
it works if i put: 123.0.123.123
any sugestions ? i want to check if the ip typed is like: xxx.xxx.xxx.xxx (x, xx, or xxx) and if the first number of every xxx isn't 0

Example: 12.237.2.124 -> correct
                73.02.21.14 -> incorrect
                84.14.013.23 -> incorrect

did you get the ideea?
thanx
0
 
LVL 84

Expert Comment

by:ozo
ID: 18870252
h=0
while [ $h -eq 0 ]; do
  if echo "$host" | egrep -e '^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$';
  then
    IFS='.'
    arr=($host)
    if [ ${arr[0]} -le 255 -a ${arr[1]} -le 255 -a ${arr[2]} -le 255 -a ${arr[3]} -le 255 ]
    then
      if [ ${arr[0]:0:1} -ne 0 -a ${arr[1]:0:1} -ne  0 -a ${arr[2]:0:1} -ne 0 ] ; then
        h=1
        IFS=''
      else
        echo "Error: The first digit cannot be 0, try again"
        read host
      fi
    else
      echo "Error: The maximum number you can write is 255, try again."
      read host
    fi
  else
    echo "Error: You MUST use only digits from 1 to 5, and the ip must be like xxx.xxx.xxx.xxx, try again."
    read host

fi
done
0
 
LVL 7

Expert Comment

by:nixfreak
ID: 18870368
h=0
while [ $h -eq 0 ]; do
        read host
        echo $host | egrep -e '^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$' >
/dev/null
        if [ "$?" -ne 0 ] ; then
                echo "Error: The ip must be like xxx.xxx.xxx.xxx, try again."
                continue
        else
                IFS='.'
                arr=($host)
                for i in 0 1 2 3 ; do
                        if [ ${arr[i]} -gt 255 ] ; then
                                echo "Error: The maximum number you can write is 255, try again"
                                continue 2
                        fi
                        echo ${arr[i]} | egrep "0[0-9]+" > /dev/null
                        if [ "$?" -eq 0 ] ; then
                                echo "Error: The first digit cannot be 0, try again"
                                continue 2
                        fi
                done
        fi
        h=1 ; echo "IP accepted!"
done
0
Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

 
LVL 7

Assisted Solution

by:nixfreak
nixfreak earned 100 total points
ID: 18870374
Typo.

h=0
while [ $h -eq 0 ]; do
        read host
        echo $host | egrep -e '^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$' > /dev/null
        if [ "$?" -ne 0 ] ; then
                echo "Error: The ip must be like xxx.xxx.xxx.xxx, try again."
                continue
        else
                IFS='.'
                arr=($host)
                for i in 0 1 2 3 ; do
                        if [ ${arr[i]} -gt 255 ] ; then
                                echo "Error: The maximum number you can write is 255, try again"
                                continue 2
                        fi
                        echo ${arr[i]} | egrep "0[0-9]+" > /dev/null
                        if [ "$?" -eq 0 ] ; then
                                echo "Error: The first digit cannot be 0, try again"
                                continue 2
                        fi
                done
        fi
        h=1 ; echo "IP accepted!"
done       
0
 
LVL 84

Accepted Solution

by:
ozo earned 400 total points
ID: 18870385
the first test could also have been
  if echo "$host" | egrep -e '^[1-9][0-9]{0,2}\.[1-9][0-9]{0,2}\.[1-9][0-9]{0,2}\.[1-9][0-9]{0,2}$';
but that does not show whats wrong in the original script
0
 

Author Comment

by:rares_dumitrescu
ID: 18872188
yes ozo, finally, "if echo "$host" | egrep -e '^[1-9][0-9]{0,2}\.[1-9][0-9]{0,2}\.[1-9][0-9]{0,2}\.[1-9][0-9]{0,2}$';"

please, if you can explain what [1-9][0-9]{0,2} or [1-9]{1,3} means, so i can learn, maybe i will need it again sometime.

thanx a lot, and have a HAPPY EASTER :)
0
 
LVL 84

Expert Comment

by:ozo
ID: 18872665
[1-9] means any character fron '1' to '9'
[1-9]{1,3} means any character fron '1' to '9' between 1 and 3 times
][0-9]{0,2} means any character fron '0' to '9' between 0 and 2 times
perl -MYAPE::Regex::Explain -e "print YAPE::Regex::Explain->new('^[1-9][0-9]{0,2}\.[1-9][0-9]{0,2}\.[1-9][0-9]{0,2}\.[1-9][0-9]{0,2}$')->explain"
0
 

Author Comment

by:rares_dumitrescu
ID: 18872844
thanx mr ozo
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
pre4 challenge 19 94
post4 challenge 28 93
Linux: disable vim auto-comment 7 96
Excel file not created as expected 7 49
Introduction: Dialogs (2) modeless dialog and a worker thread.  Handling data shared between threads.  Recursive functions. Continuing from the tenth article about sudoku.   Last article we worked with a modal dialog to help maintain informat…
Have you tried to learn about Unicode, UTF-8, and multibyte text encoding and all the articles are just too "academic" or too technical? This article aims to make the whole topic easy for just about anyone to understand.
This video will show you how to get GIT to work in Eclipse.   It will walk you through how to install the EGit plugin in eclipse and how to checkout an existing repository.
Learn how to create flexible layouts using relative units in CSS.  New relative units added in CSS3 include vw(viewports width), vh(viewports height), vmin(minimum of viewports height and width), and vmax (maximum of viewports height and width).

910 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

25 Experts available now in Live!

Get 1:1 Help Now