IO::Handle-like $body -- why getline(), not read()

[miyagawa]

confound pointed out that $fh as a file handle might not work if it's not line-ending, or performance poorly. Can we let them support read instead? Or let implementors to specify a callback that app can optionally set file handle back (like the case of AnyEvent?)

Duck typing read() and getline() on perl objects and filehandles are hard.

From PEP333:

Some operating environments provide special high-performance file- transmission facilities, such as the Unix sendfile() call. Servers and gateways may expose this functionality via an optional wsgi.file_wrapper key in the environ. An application may use this "file wrapper" to convert a file or file-like object into an iterable that it then returns, e.g.:

if 'wsgi.file_wrapper' in environ:
return environ['wsgi.file_wrapper'](filelike, block_size)
else:
return iter(lambda: filelike.read(block_size), '')

To be considered "file-like", the object supplied by the application must have a read() method that takes an optional size argument. It may have a close() method, and if so, the iterable returned by wsgi.file_wrapper must have a close() method that invokes the original file-like object's close() method.

[miyagawa]

13:12 tiarra: 13:11:26 >miyagawa< yay
13:12 tiarra: 13:11:26 >miyagawa< so I talked with nothingmuch for like half an hour
13:13 miyagawa: getline is kept. read is not because it's not easy to write read() mock
13:13 Mode: +n
13:13 Created at: 2008/04/30 00:02
13:13 miyagawa: but getline is
13:13 miyagawa: and if backends want to read binary then just use fileno to check if it's a real filehandle
13:13 miyagawa: and/or do local $/ = $bytes; to do chunking

[miyagawa]

feedback merged.