Validate an IP address - Return to menu Post: 302377407

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Top Forums Shell Programming and Scripting Validate an IP address - Return to menu Post 302377407 by Scrutinizer on Friday 4th of December 2009 02:56:30 AM

12-04-2009

Moderator

OK I brushed it up a little bit so that is handles ".1.1.1" :

Code:

#!/bin/sh
set -x
oldIFS=$IFS
while : ; do
  IFS=$oldIFS
  echo "Enter IP address"
  read quad

  IFS=.
  set -- $quad

  if [ $# -ne 4 ]; then
    echo "Must have 4 parts"
    continue
  fi

  for oct in $1 $2 $3 $4; do
    echo $oct | egrep "^[0-9]+$" >/dev/null 2>&1
    if [ "$?" -ne "0" ]; then
       echo "$oct: Not numeric"
       continue 2
    else
       if [ "$oct" -lt "0" -o "$oct" -gt "255" ]; then
          echo "$oct: Out of range"
          continue 2
       fi
    fi
  done

  echo "$quad" | grep "\.$" >/dev/null 2>&1
  if [ "$?" -eq "0" ]; then
    echo "Trailing period - invalid"
    continue
  fi

  if [ -n $1 ] || [ $1 -eq 0 ]
  then
    echo "First octet must not be zero (0)..."
    continue
  fi

  # if we're here, we're validated
  echo "$quad validates OK!"
  exit 0
done

Not my cup of tea though. Check CFA Johnson's solution:

Last edited by Scrutinizer; 12-04-2009 at 04:02 AM..

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LEARN ABOUT DEBIAN

dh_installmenu

DH_INSTALLMENU(1)						     Debhelper							 DH_INSTALLMENU(1)

NAME

       dh_installmenu - install Debian menu files into package build directories

SYNOPSIS

       dh_installmenu [debhelperoptions] [-n]

DESCRIPTION

       dh_installmenu is a debhelper program that is responsible for installing files used by the Debian menu package into package build
       directories.

       It also automatically generates the postinst and postrm commands needed to interface with the Debian menu package. These commands are
       inserted into the maintainer scripts by dh_installdeb(1).

FILES

       debian/package.menu
	   Debian menu files, installed into usr/share/menu/package in the package build directory. See menufile(5) for its format.

       debian/package.menu-method
	   Debian menu method files, installed into etc/menu-methods/package in the package build directory.

OPTIONS

       -n, --noscripts
	   Do not modify postinst/postrm scripts.

SEE ALSO

       debhelper(7) update-menus(1) menufile(5)

       This program is a part of debhelper.

AUTHOR

       Joey Hess <joeyh@debian.org>

9.20120909							    2011-09-12							 DH_INSTALLMENU(1)

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