如果文件没有以结尾,或者无法确保读取完整的第一行,这些解决方案中有几个会有问题。
def tail(file, n=1, bs=1024):
f = open(file)
f.seek(-1,2)
l = 1-f.read(1).count('\n') # If file doesn't end in \n, count it anyway.
B = f.tell()
while n >= l and B > 0:
block = min(bs, B)
B -= block
f.seek(B, 0)
l += f.read(block).count('\n')
f.seek(B, 0)
l = min(l,n) # discard first (incomplete) line if l > n
lines = f.readlines()[-l:]
f.close()
return lines
