Recursively find all PDF files in a folder that contain DOIs and display them

find_doi.py

import os
import glob
import sys

def extract_doi(filename):
    f = open(filename,'rb')
    text = f.read()
    f.close()
    start = text.find('URI(')
    if start > 0:
        end = text.index(')', start)
        print "%-20s %s" % (os.path.basename(filename), text[start+4:end-1])

def search_doi(directory):
    for item in glob.glob(os.path.join(directory,'*')):
        if os.path.isdir(item):
            search_doi(item)
        elif item.endswith('.pdf'):
            extract_doi(item)
        
if __name__ == '__main__':
    for arg in sys.argv[1:]:
        search_doi(arg)