readline() blocks after select() says there's data??

[Grant Edwards]

In article <a6tdvl$19mg$1 at nntp6.u.washington.edu>, Donn Cave wrote:
> Quoth grante at visi.com (Grant Edwards):
>| In article <mailman.1016212173.16075.python-list at python.org>, Rich Cook wrote:
> ...
>|> So do I have to read the data byte by byte using read(1) and
>|> examine each character to avoid blocking? Is there any way to
>|> find out how much data is actually waiting for me in the file
>|> object so I can read it in bigger increments, or must I call
>|> select then read(1) for every byte?
>|
>| You don't have to read it 1 byte at a time. Just call
>| f.read(1024) and it will give you however many bytes are
>| available, up to the max of 1024.  You can use a max different
>| than 1024 if you want.
> 
> I think you're making the problem worse here.
> 
>   import popen2
>   t = popen2.Popen3('echo L1; sleep 2; echo L2; sleep 2; echo L3')
>   print 'First read: ', repr(t.fromchild.read(1024))
> 
>   $ python /tmp/x
>   First read:  'L1\nL2\nL3\n'
> 
> C I/O basically sucks for this application.  When you ask for 1024,
> fread is bound to get that amount, just as it is if you ask for a
> line via fgets ("readline".)  If you omit the amount, you're asking
> for all the data, won't return until the socket's other end closes.

Sorry, with all the talk of sockets, I was thinking of the recv() call.

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