PycURL 续传功能

Question

我好像无法让RESUME_FROM这个选项正常工作。下面是我一直在测试的一些示例代码：

import os
import pycurl
import sys

def progress(total, existing, upload_t, upload_d):
    try:
        frac = float(existing)/float(total)
    except:
        frac = 0
    sys.stdout.write("\r%s %3i%%" % ("file", frac*100)  )

url = "http://launchpad.net/keryx/stable/0.92/+download/keryx_0.92.4.tar.gz"
filename = url.split("/")[-1].strip()

def test(debug_type, debug_msg):
    print "debug(%d): %s" % (debug_type, debug_msg)

c = pycurl.Curl()
c.setopt(pycurl.URL, url)
c.setopt(pycurl.FOLLOWLOCATION, 1)
c.setopt(pycurl.MAXREDIRS, 5)

# Setup writing
if os.path.exists(filename):
    f = open(filename, "ab")
    c.setopt(pycurl.RESUME_FROM, os.path.getsize(filename))
else:
    f = open(filename, "wb")
c.setopt(pycurl.WRITEDATA, f)

#c.setopt(pycurl.VERBOSE, 1)
c.setopt(pycurl.DEBUGFUNCTION, test)
c.setopt(pycurl.NOPROGRESS, 0)
c.setopt(pycurl.PROGRESSFUNCTION, progress)
c.perform()

Answer 1

其实它是正常恢复的，不过看起来像是又从头开始了，因为在进度函数里没有把文件的大小（通过os.path.getsize(filename)获取）加到已有的进度上。这只是一个小错误！:)