Simple recursive grep in python with highlighting.

pygrep.py

#!/usr/bin/env python
# see: http://i.imgur.com/X7JCr.png
import re
import os
import argparse

TEXTCHARS = ''.join(map(chr, [7,8,9,10,12,13,27] + range(0x20, 0x100)))
is_binary_string = lambda bytes: bool(bytes.translate(None, TEXTCHARS))

if __name__ == '__main__':
    parser = argparse.ArgumentParser('pygrep')
    parser.add_argument('-d', '--directory', type=str, required=False,
                        default='.', help='root directory to search')
    parser.add_argument('pattern', type=str, help='search pattern')
    args = parser.parse_args()
    pattern = re.compile(args.pattern)
    for path, _, files in os.walk(args.directory):
        for fn in files:
            filepath = os.path.join(path, fn)
            if is_binary_string(open(filepath).read(1024)):
                continue
            with open(filepath) as handle:
                for lineno, line in enumerate(handle):
                    mo = pattern.search(line)
                    if mo:
                        print("%s:%s: %s" % (filepath, lineno,
                              line.strip().replace(mo.group(), "\033[92m%s\033[0m"%
                                  mo.group())))