corrupt download with urllib2

[Peter Otten]

Ulli Horlacher wrote:

> I am currently developing a program which should run on Linux and Windows.
> Later it shall be compiled with PyInstaller. Therefore I am using Python
> 2.7
> 
> My program must download http://fex.belwue.de/download/7za.exe
> 
> I am using this code:

> It works with Linux, but not with Windows 7, where the downloaded 7za.exe
> is corrupt: it has the wrong size, 589044 instead of 587776 Bytes.
> 
> Where is my error?

>     sz = path.join(fexhome,'7za.exe')
>     szurl = "http://fex.belwue.de/download/7za.exe"
> 
>    try:
>       szo = open(sz,'w')

Open the file in binary mode to avoid the translation of "\n" into "\r\n":

        szo = open(sz, 'wb')

>     except (IOError,OSError) as e:
>       die('cannot write %s - %s' % (sz,e.strerror))

Unrelated, but I recommend that you let the exceptions bubble up for easier 
debugging.

Python is not Perl ;)

>     import urllib2
>     printf("\ndownloading %s\n",szurl)
>     try:
>       req = urllib2.Request(szurl)
>       req.add_header('User-Agent',useragent)
>       u = urllib2.urlopen(req)
>     except urllib2.URLError as e:
>       die('cannot get %s - %s' % (szurl,e.reason))
>     except urllib2.HTTPError as e:
>       die('cannot get %s - server reply: %d %s' % (szurl,e.code,e.reason))
>     if u.getcode() == 200:
>       print(u.read(),file=szo,end='')
>       szo.close()
>     else:
>       die('cannot get %s - server reply: %d' % (szurl,u.getcode()))
>