As vladb pointed out, this limits the amount of data read. If you upload a 3 GB file without using some value for the buffer size, (I think) all the 3 GB would be loaded into memory, thus probably crashing your server.

Incorrect. The third argument to read is indeed the buffer size, but not setting it will not result in all data being read at once. Instead, it will result in this error:

Not enough arguments for read

-sam

In reply to Re: Re: optimization of browser upload by samtregar
in thread optimization of browser upload by Baz

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