Learn Python the hard way series 3 :file

reading files:
example 15：
           from sys import argv
            script, filename = argv
            txt = open(filename)
            print "Here's your file %r:" % filename
            print txt.read()
            txt.close()

open目的是读取filename的目录，read才是读取内容

close() ，处理完文件后你需要将其关闭，这是很重要的一点。

close -- Closes the file. Like File->Save.
read -- Reads the contents of the file. You can assign the result to a variable.
readline -- Reads just one line of a text file.（靠找/n来查找第几行，会自动记住所到行数）
truncate -- Empties the file.
write('stuff') -- Appends "stuff" to the file.
seek(0) 找到0 byte位置

关于open(file(name[, mode[, buffering]])
    The mode can be 'r', 'w' or 'a' for reading (default), writing or appending.
    Add a 'b' to the mode for binary files.
    Add a '+' to the mode to allow simultaneous reading and writing.