#! /usr/bin/env python # Update a bunch of files according to a script.# The input file contains lines of the form <filename>:<lineno>:<text>,# meaning that the given line of the given file is to be replaced# by the given text.  This is useful for performing global substitutions# on grep output: import osimport sysimport re pat = '^([^: \t\n]+):([1-9][0-9]*):'prog = re.compile(pat) class FileObj:    def __init__(self, filename):        self.filename = filename        self.changed = 0        try:            self.lines = open(filename, 'r').readlines()        except IOError, msg:            print '*** Can\'t open "%s":' % filename, msg            self.lines = None            return        print 'diffing', self.filename     def finish(self):        if not self.changed:            print 'no changes to', self.filename            return        try:            os.rename(self.filename, self.filename + '~')            fp = open(self.filename, 'w')        except (os.error, IOError), msg:            print '*** Can\'t rewrite "%s":' % self.filename, msg            return        print 'writing', self.filename        for line in self.lines:            fp.write(line)        fp.close()        self.changed = 0     def process(self, lineno, rest):        if self.lines is None:            print '(not processed): %s:%s:%s' % (                      self.filename, lineno, rest),            return        i = eval(lineno) - 1        if not 0 <= i < len(self.lines):            print '*** Line number out of range: %s:%s:%s' % (                      self.filename, lineno, rest),            return        if self.lines[i] == rest:            print '(no change): %s:%s:%s' % (                      self.filename, lineno, rest),            return        if not self.changed:            self.changed = 1        print '%sc%s' % (lineno, lineno)        print '<', self.lines[i],        print '---'        self.lines[i] = rest        print '>', self.lines[i], def main():    if sys.argv[1:]:        try:            fp = open(sys.argv[1], 'r')        except IOError, msg:            print 'Can\'t open "%s":' % sys.argv[1], msg            sys.exit(1)    else:        fp = sys.stdin    curfile = None    while 1:        line = fp.readline()        if not line:            if curfile: curfile.finish()            break        n = prog.match(line)        if n < 0:            print 'Funny line:', line,            continue        filename, lineno = prog.group(1, 2)        if not curfile or filename <> curfile.filename:            if curfile: curfile.finish()            curfile = FileObj(filename)        curfile.process(lineno, line[n:]) if __name__ == "__main__":    main()