#! /usr/bin/env python # 1)  Regular Expressions Test##     Read a file of (extended per egrep) regular expressions (one per line),#     and apply those to all files whose names are listed on the command line.#     Basically, an 'egrep -f' simulator.  Test it with 20 "vt100" patterns#     against a five /etc/termcap files.  Tests using more elaborate patters#     would also be interesting.  Your code should not break if given hundreds#     of regular expressions or binary files to scan. # This implementation:# - combines all patterns into a single one using ( ... | ... | ... )# - reads patterns from stdin, scans files given as command line arguments# - produces output in the format <file>:<lineno>:<line># - is only about 2.5 times as slow as egrep (though I couldn't run#   Tom's test -- this system, a vanilla SGI, only has /etc/terminfo) import stringimport sysimport re def main():    pats = map(chomp, sys.stdin.readlines())    bigpat = '(' + '|'.join(pats) + ')'    prog = re.compile(bigpat)     for file in sys.argv[1:]:        try:            fp = open(file, 'r')        except IOError, msg:            print "%s: %s" % (file, msg)            continue        lineno = 0        while 1:            line = fp.readline()            if not line:                break            lineno = lineno + 1            if prog.search(line):                print "%s:%s:%s" % (file, lineno, line), def chomp(s):    return s.rstrip('\n') if __name__ == '__main__':    main()