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diff --git a/.gitignore b/.gitignore
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+build
+*.egg-info
+dist
+*project
diff --git a/README.md b/README.md
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+# Installation
+
+* Clone the `cidrchk` git repository
+* `sudo python setup.py install`
+
+If you are unable to install `cidrchk` as root, please use the following notation instead:
+
+* `python setup.py install --user`
+
+# What is cidrchk?
+
+`cidrchk` is a simple Python script with only one purpose: To inform a user whether or not their computer is connected to a particular network. For example, on your "work" laptop, you depend on autofs to automatically mount NFS directories. However, when you are off-site or not connected to your institution's VPN, you quickly realize attempting to access these data areas will cause significantly long delays (i.e. the *five minute* default timeout period)
+
+# Options
+
+```
+usage: cidrchk [-h] [--ignore IGNORE] [--debug] [--verbose] cidr [cidr ...]
+
+Detects whether or not any ethernet devices match to a defined CIDR range.
+
+positional arguments:
+  cidr                  IP range(s) to detect
+
+optional arguments:
+  -h, --help            show this help message and exit
+  --ignore IGNORE, -i IGNORE
+                        IP range(s) to ignore (Default: link-local and
+                        localhost)
+  --debug, -d
+  --verbose, -v
+```
+
+# How do I use it?
+
+Consider the following **.cshrc** example:
+
+```
+setenv PATH $HOME/bin:${PATH}
+setenv MYDATA /remote/data1
+alias badidea "cd ${MYDATA}"
+```
+
+What happens if you, out of habit, attempt to execute your favorite alias?
+
+```
+$ badidea
+[ no output, waiting for autofs to timeout ]
+```
+
+Whoops! Things didn't go as planned, so let's take a look at the same **.cshrc** example using `cidrchk`:
+
+```
+setenv PATH $HOME/bin:${PATH}
+setenv MYDATA /remote/data1
+
+set _OFFSITE = `cidrchk 10.0.0.0/20 66.55.32.0/20 >/dev/null`
+setenv OFFSITE $status
+unset _OFFSITE
+
+alias badidea "cd ${MYDATA}"
+
+if ( ${OFFSITE} ) then
+    unalias badidea
+endif
+```
+
+In the above example the following is *true*: 
+
+If 10.0.0.0/20 represents your institution's VPN address space and 66.55.32.0/20 represents your company's local intranet, and your home IP was 192.168.1.101, `cidrchk` returned a non-zero value indicating your computer was "off-site".
+
+Inversely, if your computer's IP address was 66.55.45.10 (i.e. you are in your cubicle), `cidrchk` would return zero indicating your computer was "on-site".
+
+## Other Possiblities
+
+Issuing `-v` to `cidrchk` will echo the return value to the console, resulting in slightly more cleaner code:
+
+```
+setenv OFFSITE `cidrchk -v 10.0.0.0/24 66.55.32.0/20`
+
+if ( ${OFFSITE} ) then
+    # do something clever to prevent personal hardship
+endif
+```
+
+## How do I use BASH with cidrchk?
+
+The notation required for `cidrchk` to use BASH is nearly identical to TCSH:
+
+```
+_OFFSITE=$(cidrchk 10.0.0.0/24 66.55.32.0/20 >/dev/null)
+export OFFSITE=$?
+
+if (( ${OFFSITE} )); then
+    #do something clever to prevent personal hardship
+fi
+```
+
+# Bug Reporting
+
+Submit bug reports via this project's issue tracker: https://bitbucket.org/jhunkeler/cidrchk/issues
+
+Please remember to include your computer's operating system, the name of the shell you executed `cidrchk` from, the output of `cidrchk -d`, and any relevant code snippets you may have.
+
diff --git a/cidrchk b/cidrchk
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+++ b/cidrchk
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+#!/usr/bin/env python
+# Copyright (c) 2014, Joseph Hunkeler <jhunkeler at gmail.com>
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+# 1. Redistributions of source code must retain the above copyright notice, this
+#   list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright notice,
+#   this list of conditions and the following disclaimer in the documentation
+#   and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+class ExitCode(object):
+    SUCCESS, FAIL, NO_MODULE, NO_INTERFACE = range(4)
+
+try:
+    import argparse
+except ImportError:
+    print('argparse module required.')
+    exit(ExitCode.NO_MODULE)
+
+try:
+    import netifaces
+except ImportError:
+    print('netifaces module required.')
+    exit(ExitCode.NO_MODULE)
+
+try:
+    from netaddr import IPNetwork
+except ImportError:
+    print('netaddr module required.')
+    exit(ExitCode.NO_MODULE)
+
+
+DEBUG = False
+VERBOSE = False
+
+def info(ignore, accept):
+    status = {'IGNORED':[], 'DETECTED':[], 'OTHER':[]}
+    for interface in netifaces.interfaces():
+        ignored = False
+        detected = False
+
+        try:
+            addr = netifaces.ifaddresses(interface)
+            if not netifaces.AF_INET in addr:
+                continue
+        except:
+            return None
+
+        for iface in addr[netifaces.AF_INET]:
+            if not 'addr' in iface:
+                continue
+
+            address = iface['addr']
+            for ip_range in ignore:
+                if address in ip_range:
+                    ignored = True
+
+            for ip_range in accept:
+                if address in ip_range:
+                    detected = True
+
+            if ignored:
+                if DEBUG:
+                    print('Ignored: {0} on {1}'.format(address, interface))
+                status['IGNORED'].append(address)
+                continue
+
+            if detected:
+                if DEBUG:
+                    print('Detected: {0} on {1}'.format(address, interface))
+                status['DETECTED'].append(address)
+                continue
+            
+            if DEBUG:
+                print('Detected (non-match): {0} on {1}'.format(address, interface))
+            status['OTHER'].append(address)
+    return status
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description='Detects whether or not any ethernet devices match to a defined CIDR range.')
+    parser.add_argument('--ignore', '-i', action='append', default=[ IPNetwork('127.0.0.0/8'), IPNetwork('169.254.0.0/16') ], type=IPNetwork, help='IP range(s) to ignore (Default: link-local and localhost)')
+    parser.add_argument('--debug', '-d', action='store_true', default=False)
+    parser.add_argument('--verbose', '-v', action='store_true', default=False)
+    parser.add_argument('cidr', nargs="+", type=IPNetwork, help='IP range(s) to detect')
+    args = parser.parse_args()
+    
+    DEBUG = args.debug
+    VERBOSE = args.verbose
+
+    status = info(args.ignore, args.cidr)
+
+    if status is None:
+        if DEBUG:
+            print("No ethernet interface detected")
+        if VERBOSE:
+            print(ExitCode.NO_INTERFACE)
+        exit(ExitCode.NO_INTERFACE)
+
+    if not status['DETECTED']:
+        if DEBUG:
+            print("No ethernet interface is operating at the defined range")
+        if VERBOSE:
+            print(ExitCode.FAIL)
+        exit(ExitCode.FAIL)
+
+    if DEBUG:
+        print("A network interface matched defined range")
+    if VERBOSE:
+        print(ExitCode.SUCCESS)
+
+    exit(ExitCode.SUCCESS)
diff --git a/setup.py b/setup.py
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+++ b/setup.py
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+import os
+from setuptools import setup
+
+setup(
+    name = 'cidrchk',
+    version = '1.0.0',
+    author = 'Joseph Hunkeler',
+    author_email = 'jhunkeler@gmail.com',
+    description = ('A simple "Is my computer on this subnet?" detection script.'),
+    license = 'BSD',
+    keywords = 'cidrchk detect network interface ethernet',
+    zip_safe = True,
+    scripts = [
+        'cidrchk',
+    ],
+    install_requires = [
+        'netaddr',
+        'netifaces',
+        'argparse',
+    ],
+    classifiers = [
+        'Development Status :: 5 - Production/Stable',
+        'Topic :: Utilities',
+        'License :: OSI Approved :: BSD License',
+    ]
+)
diff --git a/test_cidrchk.sh b/test_cidrchk.sh
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+#!/bin/bash
+program=./cidrchk
+args="$@"
+
+if [ -z "$args" ]; then
+    echo "No CIDR range(s) defined"
+    exit 1
+fi
+
+$program $args
+retval=$?
+
+case "$retval" in
+    0)
+        echo "On net"
+    ;;
+    1)
+        echo "Off net"
+    ;;
+    2)
+        echo "Module import failure detected"
+    ;;
+    3)
+        echo "No network interfaces detected"
+    ;;
+    *)
+        echo "Unknown failure"
+    ;;
+esac