head.py

#!/usr/bin/env python
# Author:  Yotam Medini  [email protected] -- Created: 2006/April/06
# Linux-like 'head'

import sys


def head(f, n):
    li = 0
    line = f.readline()
    while li < n and line != '':
       sys.stdout.write(line)
       line = f.readline()
       li += 1


# Program begin
f = sys.stdin   # default file
n = 10          # default number of lines

nArgs = len(sys.argv)
ai = 1

# check for user given number of lines
if ai + 1 < nArgs  and sys.argv[ai] == '-n':
    n = int(sys.argv[ai + 1])
    ai += 2

# check for user given file name
if ai < nArgs:
    fn = sys.argv[ai]
    f = open(fn)

head(f, n)
sys.exit(0)